Polyethylene compositions and articles made therefrom

ABSTRACT

Polyethylene compositions including at least 65 wt % ethylene derived units and from 0 to 35 wt % of C 3 -C 12  olefin comonomer derived units, based upon the total weight of the polyethylene composition are provided. The polyethylene compositions have a) an RCI,m of 100 kg/mol or greater and one or both of: b) a Tw 1 -Tw 2  value of from −16 to −38° C.; and c) an Mw 1 /Mw 2  value of at least 0.9. The polyethylene compositions may be used to manufacture articles such as films.

CROSS-REFERENCE OF RELATED APPLICATIONS

This application claims the benefit of Ser. No. 62/585,223, filed onNov. 13, 2017, the disclosure of which is incorporated herein byreference in its entirety.

FIELD OF THE INVENTION

The present disclosure relates to polyethylene (PE) compositions madefrom mixed metallocene catalyst systems and articles, such as films,made therefrom.

BACKGROUND OF THE INVENTION

Olefin polymerization catalysts are of great use in industry to producepolyolefin polymers and these polymers have revolutionized virtuallyevery aspect of the modern world. Hence, there is strong interest infinding new catalyst systems to use in polymerization processes thatincrease the commercial usefulness of the catalyst systems and allow theproduction of polyolefin polymers having improved properties or a newcombination of properties.

In particular, much effort has been placed in understanding how thecomonomer is distributed along the polymer carbon chain or simplypolymer chain of a polyolefin polymer. For example, the compositiondistribution of an ethylene alpha-olefin copolymer refers to thedistribution of comonomer (short chain branches) among the moleculesthat comprise the polyethylene polymer. When the amount of short chainbranches varies among the polymer carbon chain, the polymer or resin issaid to have a Broad Composition Distribution (BCD). When the amount ofcomonomer per about 1000 carbons is similar among the polyethylenemolecules of different polymer chain lengths or molecular weights, thecomposition distribution is said to be “narrow” or have a NarrowComposition Distribution (NCD).

The composition distribution is known to influence the properties ofcopolymers, for example, extractables content, environmental stresscrack resistance, heat sealing, dart drop impact resistance, and tearresistance or strength. The composition distribution of a polyolefin maybe readily measured by methods known in the art, for example,Temperature Raising Elution Fractionation (TREF) or CrystallizationAnalysis Fractionation (CRYSTAF). See, for example, U.S. Pat. No.8,378,043, Col. 3 and Col. 4.

Ethylene alpha-olefin copolymers may be produced in a low pressurereactor, utilizing, for example, solution, slurry, and/or gas phasepolymerization processes. Polymerization takes place in the presence ofactivated catalyst systems such as those employing a Ziegler-Nattacatalyst, a chromium based catalyst, a vanadium catalyst, a metallocenecatalyst, a mixed catalyst (i.e., two or more different catalystsco-supported on the same carrier such as a bimodal catalyst), otheradvanced catalysts, or combinations thereof. In general, these catalystswhen used in a catalyst system all produce a variety of polymer chainsin a polyolefin polymer composition that vary in molecular weight andcomonomer incorporation. In some cases, this variation becomes a“signature” to the catalyst itself.

For example, it is generally known in the art that a polyolefin'scomposition distribution is largely dictated by the type of catalystused. For example, Broad Composition Distribution or BCD refers topolymers in which the length of the molecules would be substantially thesame but the amount of the comonomer would vary along the length, forexample, for an ethylene-hexene copolymer, hexene distribution variesfrom low to high while the molecular weight is roughly the same or thePolydispersity Index (PDI) is narrow.

Polymers made with Zeigler Natta catalysts are considered to be“conventional” in which the composition distribution is broad but thehigh molecular weight fractions are higher density (i.e., lesscomonomer) than the lower molecular weight fraction (high comonomer).

In contrast, metallocene catalysts typically produce a polyolefinpolymer composition with an NCD. A metallocene catalyst is generally ametal complex of a transitional metal, typically, a Group 4 metal, andone or more cyclopentadienyl (Cp) ligands or rings. As stated above, NCDgenerally refers to the comonomer being evenly distributed or not varymuch along the polymer chain. An illustration is provided as FIG. 1 a.

More recently, a third distribution has been described for a polyolefinpolymer composition having a Broad Orthogonal Composition Distribution(BOCD) in which the comonomer is incorporated predominantly in the highmolecular weight chains. A substituted hafnocene catalyst has been notedto produce this type of distribution. See, for example, U.S. Pat. Nos.6,242,545, 6,248,845, 6,528,597, 6,936,675, 6,956,088, 7,172,816,7,179,876, 7,381,783, 8,247,065, 8,378,043, 8,476,392; U.S. PatentApplication Publication No. 2015/0291748; and Ser. No. 62/461,104, filedFeb. 20, 2017, entitled Supported Catalyst Systems and Processes for UseThereof. An illustration is provided as FIG. 1b . This distribution hasbeen noted for its improved physical properties, for example, ease infabrication of end-use articles as well as stiffness and toughness inmultiple applications such as films that can be measured by dart dropimpact resistance and tear resistance or strength.

As taught by U.S. Pat. No. 8,378,043, BOCD refers to incorporating thecomonomer predominantly in the high molecular weight chains. Thedistribution of the short chain branches can be measured, for example,using Temperature Raising Elution Fractionation (TREF) in connectionwith a Light Scattering (LS) detector to determine the weight averagemolecular weight of the molecules eluted from the TREF column at a giventemperature. The combination of TREF and LS (TREF-LS) yields informationabout the breadth of the composition distribution and whether thecomonomer content increases, decreases, or is uniform across the chainsof different molecular weights.

In another patent, U.S. Pat. No. 9,290,593 ('593 patent) teaches thatthe term “BOCD” is a novel terminology that is currently developed andrelates to a polymer structure. The term “BOCD structure” means astructure in which the content of the comonomer such as alpha olefins ismainly high at a high molecular weight main chain, that is, a novelstructure in which the content of a short chain branching (SCB) isincreased as moving toward the high molecular weight. The '593 patentalso teaches a BOCD Index. The BOCD Index may be defined by thefollowing equation:BOCD Index=(Content of SCB at the high molecular weight side−Content ofSCB at the low molecular weight side)/(Content of SCB at the lowmolecular weight side)wherein the “Content of SCB at the high molecular weight side” means thecontent of the SCB (the number of branches/1000 carbon atoms) includedin a polymer chain having a molecular weight of Mw of the polyolefin ormore and 1.3×Mw or less, and the “Content of SCB at the low molecularweight side” means the content of the SCB (the number of branches/1000carbon atoms) included in a polymer chain having a molecular weight of0.7×Mw of the polyolefin or more and less than Mw. The BOCD Indexdefined by equation above may be in the range of 1 to 5, preferably 2 to4, more preferably 2 to 3.5. See, also, FIGS. 1 and 2 of the '593 patent(characterizing BOCD polymer structures using GPC-FTIR data).

BOCD behavior in a polymer composition has been associated with a goodbalance of mechanical and optical properties and has been an importantgoal in the development of new polymer products. For example, Linear LowDensity Polyethylene (LLDPE) film applications and products strive for agood balance of stiffness, toughness, optical properties (e.g., haze andgloss) and processability. For some LLDPE film applications, sealingperformance is also important. Sealing performance is affected mainly bydensity, it improves as density gets lower, but density has the oppositeeffect on stiffness. Therefore, to achieve a balanced performance, thereis usually a trade-off between stiffness and sealing performance. Thus,to improve sealing performance while maintaining good stiffness remainsa challenge. Past efforts have shown that namely molecular weightdistribution and comonomer distribution interdependence (MwD×CD) has astrong effect on sealing performance, with narrow CD resin bymetallocene catalyst outperforming broad CD resin by conventionalcatalysts. Other background references include U.S. Patent PublicationNo. 2009/0156764 and U.S. Pat. Nos. 7,119,153, 7,547,754, 7,572,875,7,625,982, 8,383,754, 8,691,715, 8,722,567, 8,846,841, 8,940,842,9,006,367, 9,096,745, 9,115,229, 9,181,369, 9,181,370, 9,217,049,9,334,350, 9,447,265 and WO 2015/123164.

Thus, there is a need for polyethylene compositions that can exhibit,for example, BCD or BOCD behavior to produce LLDPE film products orother useful articles with a good balance of one or more of highstiffness, toughness and sealing performance, as well as good opticalproperties (e.g., haze and gloss).

SUMMARY OF THE INVENTION

In a class of embodiments, the invention provides for a polyethylenecomposition comprising at least 65 wt % ethylene derived units and from0 to 35 wt % of C₃-C₁₂ olefin comonomer derived units, based upon thetotal weight of the polyethylene composition; wherein the polyethylenecomposition has:

-   -   a) an RCI,m of 100 kg/mol or greater, such as 150 kg/mol or        greater;

and one or both of:

-   -   b) a Tw₁-Tw₂ value of from −16 to −38° C.; and    -   c) an Mw₁/Mw₂ value of at least 0.9, such as at least 2 or at        least 3;

and one or more of the following:

-   -   d) a density of from 0.890 g/cm³ to 0.940 g/cm³;    -   e) a melt index (MI) of from 0.1 g/10 min to 30 g/10 min;    -   f) a melt index ratio (I₂₁/I₂) of from 10 to 90, such 30 to 55,        or 35 to 45;    -   g) an M_(w)/M_(n) of from 2 to 16, such as 9 to 14, or 10 to 14;    -   h) an M_(z)/M_(w) of from 2.5 to 5.0;    -   i) an M_(z)/M_(n) of from 10 to 50, such as 25 to 50, or 25 to        45; and    -   j) a g′(vis) of 0.90 or greater.

In another class of embodiments, the invention provides for articlesmade from the polyethylene composition and processes for making thesame.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1a and FIG. 1b are illustrations of polyolefin's compositiondistribution characteristics: FIG. 1a is Polyolefin with narrowcomposition distribution (NCD); FIG. 1b is Polyolefin with BroadOrthogonal Composition Distribution (BOCD).

FIG. 2 is a plot of the average MD/TD film modulus as a function ofresins density for comparative and inventive examples.

FIG. 3 is a plot illustrating the calculations used to determine CFCresults where, the x-axis represents the elution temperature incentigrade, while the right hand y-axis represents the value of theintegral of the weights of polymer that have been eluted up to anelution temperature.

FIG. 4 is a plot illustrating the calculations used to determine CFCresults where, the x-axis represents the elution temperature incentigrade, while the right hand y-axis represents the value of theintegral of the weights of polymer that have been eluted up to anelution temperature.

FIG. 5 is a graph of Mw1/Mw2 versus Tw1-Tw2 (° C.).

DETAILED DESCRIPTION

Before the present compounds, components, compositions, and/or methodsare disclosed and described, it is to be understood that unlessotherwise indicated this invention is not limited to specific compounds,components, compositions, reactants, reaction conditions, ligands,metallocene structures, catalyst structures, or the like, as such mayvary, unless otherwise specified. It is also to be understood that theterminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting.

In several classes of embodiments of the invention, the presentdisclosure is directed to catalyst systems and their use inpolymerization processes to produce polyolefin polymers such aspolyethylene polymers and polypropylene polymers. In another class ofembodiments, the present disclosure is directed to polymerizationprocesses to produce polyolefin polymers from catalyst systemscomprising the product of the combination of one or more olefinpolymerization catalysts, at least one activator, and at least onesupport.

In particular, the present disclosure is directed to a polymerizationprocess to produce a polyethylene polymer, the process comprisingcontacting a catalyst system comprising the product of the combinationof one or more metallocene catalysts, at least one activator, and atleast one support, with ethylene and one or more C₃-C₁₀ alpha-olefincomonomers under polymerizable conditions.

Definitions

For purposes of this invention and the claims hereto, the numberingscheme for the Periodic Table Groups is according to the new notation ofthe IUPAC Periodic Table of Elements.

As used herein, “olefin polymerization catalyst(s) refers to anycatalyst, typically an organometallic complex or compound that iscapable of coordination polymerization addition where successivemonomers are added in a monomer chain at the organometallic activecenter.

The terms “substituent,” “radical,” “group,” and “moiety” may be usedinterchangeably.

As used herein, and unless otherwise specified, the term “C_(n)” meanshydrocarbon(s) having n carbon atom(s) per molecule, wherein n is apositive integer.

As used herein, and unless otherwise specified, the term “hydrocarbon”means a class of compounds containing hydrogen bound to carbon, andencompasses (i) saturated hydrocarbon compounds, (ii) unsaturatedhydrocarbon compounds, and (iii) mixtures of hydrocarbon compounds(saturated and/or unsaturated), including mixtures of hydrocarboncompounds having different values of n.

For purposes of this invention and claims thereto, unless otherwiseindicated, the term “substituted” means that a hydrogen group has beenreplaced with a heteroatom, or a heteroatom containing group (such ashalogen (such as Br, Cl, F or I) or at least one functional group suchas NR*₂, OR*, SeR*, TeR*, PR*₂, AsR*₂, SbR*₂, SR*, BR*₂, SiR*₃, GeR*₃,SnR*₃, PbR*₃, and the like, or where at least one heteroatom has beeninserted within a hydrocarbyl ring), or a hydrocarbyl group, except thatsubstituted hydrocarbyl is a hydrocarbyl in which at least one hydrogenatom of the hydrocarbyl has been substituted with at least oneheteroatom or heteroatom containing group, such as halogen (such as Br,Cl, F or I) or at least one functional group such as NR*₂, OR*, SeR*,TeR*, PR*₂, AsR*₂, SbR*₂, SR*, BR*₂, SiR*₃, GeR*₃, SnR*₃, PbR*₃, and thelike, or where at least one heteroatom has been inserted within ahydrocarbyl ring.

The terms “hydrocarbyl radical,” “hydrocarbyl,” “hydrocarbyl group,”“alkyl radical,” and “alkyl” are used interchangeably throughout thisdocument. Likewise, the terms “group,” “radical,” and “substituent,” arealso used interchangeably in this document. For purposes of thisdisclosure, “hydrocarbyl radical” is defined to be C₁-C₁₀₀ radicals,that may be linear, branched, or cyclic, and when cyclic, aromatic ornon-aromatic. Examples of such radicals include, but are not limited to,methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl,tert-butyl, pentyl, iso-amyl, hexyl, octyl cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl, cyclooctyl, and the like including theirsubstituted analogues.

As used herein, and unless otherwise specified, the term “alkyl” refersto a saturated hydrocarbon radical having from 1 to 12 carbon atoms(i.e., C₁-C₁₂ alkyl), particularly from 1 to 8 carbon atoms (i.e., C₁-C₈alkyl), particularly from 1 to 6 carbon atoms (i.e., C₁-C₆ alkyl), andparticularly from 1 to 4 carbon atoms (i.e., C₁-C₄ alkyl). Examples ofalkyl groups include, but are not limited to, methyl, ethyl, propyl,butyl, pentyl, hexyl, heptyl, octyl, decyl, and so forth. The alkylgroup may be linear, branched or cyclic. “Alkyl” is intended to embraceall structural isomeric forms of an alkyl group. For example, as usedherein, propyl encompasses both n-propyl and isopropyl; butylencompasses n-butyl, sec-butyl, isobutyl and tert-butyl and so forth. Asused herein, “C₁ alkyl” refers to methyl (—CH₃), “C₂ alkyl” refers toethyl (—CH₂CH₃), “C₃ alkyl” refers to propyl (—CH₂CH₂CH₃) and “C₄ alkyl”refers to butyl (e.g., —CH₂CH₂CH₂CH₃, —(CH₃)CHCH₂CH₃, —CH₂CH(CH₃)₂,etc.). Further, as used herein, “Me” refers to methyl, and “Et” refersto ethyl, “i-Pr” refers to isopropyl, “t-Bu” refers to tert-butyl, and“Np” refers to neopentyl.

As used herein, and unless otherwise specified, the term “alkylene”refers to a divalent alkyl moiety containing 1 to 12 carbon atoms (i.e.,C₁-C₁₂ alkylene) in length and meaning the alkylene moiety is attachedto the rest of the molecule at both ends of the alkyl unit. For example,alkylenes include, but are not limited to, —CH₂—, —CH₂CH₂—,—CH(CH₃)CH₂—, —CH₂CH₂CH₂—, etc. The alkylene group may be linear orbranched.

As used herein, and unless otherwise specified, the term “alkenyl”refers to an unsaturated hydrocarbon radical having from 2 to 12 carbonatoms (i.e., C₂-C₁₂ alkenyl), particularly from 2 to 8 carbon atoms(i.e., C₂-C₈ alkenyl), particularly from 2 to 6 carbon atoms (i.e.,C₂-C₆ alkenyl), and having one or more (e.g., 2, 3, etc.,) carbon-carbondouble bonds. The alkenyl group may be linear, branched or cyclic.Examples of alkenyls include, but are not limited to ethenyl (vinyl),2-propenyl, 3-propenyl, 1,4-pentadienyl, 1,4-butadienyl, 1-butenyl,2-butenyl and 3-butenyl. “Alkenyl” is intended to embrace all structuralisomeric forms of an alkenyl. For example, butenyl encompasses1,4-butadienyl, 1-butenyl, 2-butenyl and 3-butenyl, etc.

As used herein, and unless otherwise specified, the term “alkenylene”refers to a divalent alkenyl moiety containing 2 to about 12 carbonatoms (i.e., C₂-C₁₂ alkenylene) in length and meaning that the alkylenemoiety is attached to the rest of the molecule at both ends of the alkylunit. For example, alkenylenes include, but are not limited to, —CH═CH—,—CH═CHCH₂—, —CH═CH═CH—, —CH₂CH₂CH═CHCH₂—, etc. The alkenylene group maybe linear or branched.

As used herein, and unless otherwise specified, the term “alkynyl”refers to an unsaturated hydrocarbon radical having from 2 to 12 carbonatoms (i.e., C₂-C₁₂ alkynyl), particularly from 2 to 8 carbon atoms(i.e., C₂-C₈ alkynyl), particularly from 2 to 6 carbon atoms (i.e.,C₂-C₆ alkynyl), and having one or more (e.g., 2, 3, etc.) carbon-carbontriple bonds. The alkynyl group may be linear, branched or cyclic.Examples of alkynyls include, but are not limited to ethynyl,1-propynyl, 2-butynyl, and 1,3-butadiynyl. “Alkynyl” is intended toembrace all structural isomeric forms of an alkynyl. For example,butynyl encompasses 2-butynyl, and 1,3-butadiynyl and propynylencompasses 1-propynyl and 2-propynyl (propargyl).

As used herein, and unless otherwise specified, the term “alkynylene”refers to a divalent alkynyl moiety containing 2 to about 12 carbonatoms (i.e., C₂-C₁₂ alkenylene) in length and meaning that the alkylenemoiety is attached to the rest of the molecule at both ends of the alkylunit. For example, alkenylenes include, but are not limited to, —C≡C—,—C≡CCH₂—, —C≡CCH₂—C≡C—, —CH₂CH₂C≡CCH₂—. The alkynylene group may belinear or branched.

As used herein, and unless otherwise specified, the term “alkoxy” refersto —O— alkyl containing from 1 to about 10 carbon atoms. The alkoxy maybe straight-chain or branched-chain. Non-limiting examples includemethoxy, ethoxy, propoxy, butoxy, isobutoxy, tert-butoxy, pentoxy, andhexoxy. “C₁ alkoxy” refers to methoxy, “C₂ alkoxy” refers to ethoxy, “C₃alkoxy” refers to propoxy and “C₄ alkoxy” refers to butoxy. Further, asused herein, “OMe” refers to methoxy and “OEt” refers to ethoxy.

As used herein, and unless otherwise specified, the term “aromatic”refers to unsaturated cyclic hydrocarbons having a delocalizedconjugated π system and having from 5 to 20 carbon atoms (aromaticC₅-C₂₀ hydrocarbon), particularly from 5 to 12 carbon atoms (aromaticC₅-C₁₂ hydrocarbon), and particularly from 5 to 10 carbon atoms(aromatic C₅-C₁₂ hydrocarbon). Exemplary aromatics include, but are notlimited to benzene, toluene, xylenes, mesitylene, ethylbenzenes, cumene,naphthalene, methylnaphthalene, dimethylnaphthalenes, ethylnaphthalenes,acenaphthalene, anthracene, phenanthrene, tetraphene, naphthacene,benzanthracenes, fluoranthrene, pyrene, chrysene, triphenylene, and thelike, and combinations thereof.

Unless otherwise indicated, where isomers of a named alkyl, alkenyl,alkoxy, or aryl group exist (e.g., n-butyl, iso-butyl, sec-butyl, andtert-butyl) reference to one member of the group (e.g., n-butyl) shallexpressly disclose the remaining isomers (e.g., iso-butyl, sec-butyl,and tert-butyl) in the family. Likewise, reference to an alkyl, alkenyl,alkoxide, or aryl group without specifying a particular isomer (e.g.,butyl) expressly discloses all isomers (e.g., n-butyl, iso-butyl,sec-butyl, and tert-butyl).

As used herein, the term “hydroxyl” refers to an —OH group.

As used herein, “oxygenate” refers to a saturated, unsaturated, orpolycyclic cyclized hydrocarbon radical containing from 1 to 40 carbonatoms and further containing one or more oxygen heteroatoms.

As used herein, “aluminum alkyl adducts” refers to the reaction productof aluminum alkyls and/or alumoxanes with quenching agents, such aswater and/or methanol.

An “olefin,” alternatively referred to as “alkene,” is a linear,branched, or cyclic compound of carbon and hydrogen having at least onedouble bond. For purposes of this specification and the claims appendedthereto, when a polymer or copolymer is referred to as comprising anolefin, the olefin present in such polymer or copolymer is thepolymerized form of the olefin. For example, when a copolymer is said tohave an “ethylene” content of 35 wt % to 55 wt %, it is understood thatthe mer unit in the copolymer is derived from ethylene in thepolymerization reaction and said derived units are present at 35 wt % to55 wt %, based upon the weight of the copolymer.

A “polymer” has two or more of the same or different mer units. A“homopolymer” is a polymer having mer units that are the same. A“copolymer” is a polymer having two or more mer units that are distinctor different from each other. A “terpolymer” is a polymer having threemer units that are distinct or different from each other. “Distinct” or“different” as used to refer to mer units indicates that the mer unitsdiffer from each other by at least one atom or are differentisomerically. Accordingly, the definition of copolymer, as used herein,includes terpolymers and the like. An “ethylene polymer” or “ethylenecopolymer” is a polymer or copolymer comprising at least 50 mol %ethylene derived units, a “propylene polymer” or “propylene copolymer”is a polymer or copolymer comprising at least 50 mol % propylene derivedunits, and so on.

“Polymerizable conditions” refer those conditions including a skilledartisan's selection of temperature, pressure, reactant concentrations,optional solvent/diluents, reactant mixing/addition parameters, andother conditions within at least one polymerization reactor that areconducive to the reaction of one or more olefin monomers when contactedwith an activated olefin polymerization catalyst to produce the desiredpolyolefin polymer through typically coordination polymerization.

The term “continuous” means a system that operates without interruptionor cessation. For example a continuous process to produce a polymerwould be one where the reactants are continually introduced into one ormore reactors and polymer product is continually withdrawn.

A “catalyst composition” or “catalyst system” is the combination of atleast two catalyst compounds, a support material, an optional activator,and an optional co-activator. For the purposes of this invention and theclaims thereto, when catalyst systems or compositions are described ascomprising neutral stable forms of the components, it is well understoodby one of ordinary skill in the art, that the ionic form of thecomponent is the form that reacts with the monomers to produce polymers.When it is used to describe such after activation, it means the support,the activated complex, and the activator or other charge-balancingmoiety. The transition metal compound may be neutral as in aprecatalyst, or a charged species with a counter ion as in an activatedcatalyst system.

Coordination polymerization is an addition polymerization in whichsuccessive monomers are added to or at an organometallic active centerto create and/or grow a polymer chain.

The terms “cocatalyst” and “activator” are used herein interchangeablyand are defined to be any compound which can activate any one of thecatalyst compounds herein by converting the neutral catalyst compound toa catalytically active catalyst compound cation.

The term “contact product” or “the product of the combination of” isused herein to describe compositions wherein the components arecontacted together in any order, in any manner, and for any length oftime. For example, the components can be contacted by blending ormixing. Further, contacting of any component can occur in the presenceor absence of any other component of the compositions described herein.Combining additional materials or components can be done by any suitablemethod. Further, the term “contact product” includes mixtures, blends,solutions, slurries, reaction products, and the like, or combinationsthereof. Although “contact product” can include reaction products, it isnot required for the respective components to react with one another orreact in the manner as theorized. Similarly, the term “contacting” isused herein to refer to materials which may be blended, mixed, slurried,dissolved, reacted, treated, or otherwise contacted in some othermanner.

“BOCD” refers to a Broad Orthogonal Composition Distribution in whichthe comonomer of a copolymer is incorporated predominantly in the highmolecular weight chains or species of a polyolefin polymer orcomposition. The distribution of the short chain branches can bemeasured, for example, using Temperature Raising Elution Fractionation(TREF) in connection with a Light Scattering (LS) detector to determinethe weight average molecular weight of the molecules eluted from theTREF column at a given temperature. The combination of TREF and LS(TREF-LS) yields information about the breadth of the compositiondistribution and whether the comonomer content increases, decreases, oris uniform across the chains of different molecular weights of polymerchains. BOCD has been described, for example, in U.S. Pat. No.8,378,043, Col. 3, line 34, bridging Col. 4, line 19, and U.S. Pat. No.8,476,392, line 43, bridging Col. 16, line 54.

The breadth of the composition distribution is characterized by theT₇₅-T₂₅ value, wherein T₂₅ is the temperature at which 25% of the elutedpolymer is obtained and T₇₅ is the temperature at which 75% of theeluted polymer is obtained in a TREF experiment as described herein. Thecomposition distribution is further characterized by the F₈₀ value,which is the fraction of polymer that elutes below 80° C. in a TREF-LSexperiment as described herein. A higher F₈₀ value indicates a higherfraction of comonomer in the polymer molecule. An orthogonal compositiondistribution is defined by a M₆₀/M₉₀ value that is greater than 1,wherein M₆₀ is the molecular weight of the polymer fraction that elutesat 60° C. in a TREF-LS experiment and M₉₀ is the molecular weight of thepolymer fraction that elutes at 90° C. in a TREF-LS experiment asdescribed herein.

In a class of embodiments, the polymers as described herein may have aBOCD characterized in that the T₇₅-T₂₅ value is 1 or greater, 2.0 orgreater, 2.5 or greater, 4.0 or greater, 5.0 or greater, 7.0 or greater,10.0 or greater, 11.5 or greater, 15.0 or greater, 17.5 or greater, 20.0or greater, 25.0 or greater, 30.0 or greater, 35.0 or greater, 40.0 orgreater, or 45.0 or greater, wherein T₂₅ is the temperature at which 25%of the eluted polymer is obtained and T₇₅ is the temperature at which75% of the eluted polymer is obtained in a TREF experiment as describedherein.

The polymers as described herein may further have a BOCD characterizedin that M₆₀/M₉₀ value is 1.5 or greater, 2.0 or greater, 2.25 orgreater, 2.50 or greater, 3.0 or greater, 3.5 or greater, 4.0 orgreater, 4.5 or greater, or 5.0 or greater, wherein M₆₀ is the molecularweight of the polymer fraction that elutes at 60° C. in a TREF-LSexperiment and M₉₀ is the molecular weight of the polymer fraction thatelutes at 90° C. in a TREF-LS experiment as described herein.

Olefin Polymerization Catalysts

Metallocene Catalysts

The catalyst system useful herein is a mixed metallocene catalyst systemcomprising two or more different metallocene catalyst compounds, atleast one activator, and at least one support. Alternately, the catalystsystem useful herein is a mixed metallocene catalyst system comprisingone, two or more different metallocene catalyst compounds represented byformula (A) below, one, two or more different metallocene catalystcompounds represented by formula (B) below, at least one activator, andat least one support.

Preferably the first metallocene catalyst compound is represented by theformula (A):Cp ^(A) Cp ^(B) M′X′ _(n)wherein,Cp^(A) is a cyclopentadienyl group which may be substituted orunsubstituted, provided that Cp^(A) is substituted with at least one R**group, where R** is a group containing at least three carbon or siliconatoms, preferably R** is a C₃ to C₁₂ alkyl group, preferably R** is alinear C₃ to C₁₂ alkyl group (such as n-propyl, n-butyl, n-pentyl,n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl or n-dodecyl),and Cp^(A) is optionally also independently substituted by one, two,three, or four R″ groups;Cp^(B) is a cyclopentadienyl group which may be substituted orunsubstituted, substituted by one, two, three, four, or five R″ groupsor R** groups;M′ is selected from the group consisting of Groups 3 through 12 atomsand lanthanide Group atoms, preferably M is a group 4 metal, such as Hf,Zr, or Ti, preferably Hf;each X′ is, independently, a univalent anionic ligand, or two X′ arejoined and bound to the metal atom to form a metallocycle ring, or twoX′ are joined to form a chelating ligand, a diene ligand, or analkylidene ligand (preferably each X′ is independently, halogen or C₁ toC₁₂ alkyl or C₅ to C₁₂ aryl, such as Br, Cl, I, Me, Et, Pr, Bu, Ph);n is 0, 1, 2, 3, or 4, preferably n is 2; andeach R″ is independently selected from the group consisting ofhydrocarbyl, substituted hydrocarbyl, heteroatom, or heteroatomcontaining group.

In a preferred embodiment of the invention, M is Hf.

In a preferred embodiment of the invention, Cp^(A) and Cp^(B) are eachsubstituted with at least one R** group, preferably n-propyl or n-butyl.

In a preferred embodiment of the invention, each R″ is independentlyselected from the group consisting of alkyl, substituted alkyl,heteroalkyl, alkenyl, substituted alkenyl, heteroalkenyl, alkynyl,substituted alkynyl, heteroalkynyl, alkoxy, aryloxy, alkylthio,arylthio, aryl, substituted aryl, heteroaryl, aralkyl, aralkylene,alkaryl, alkarylene, haloalkyl, haloalkenyl, haloalkynyl, heteroalkyl,heterocycle, heteroaryl, a heteroatom-containing group, hydrocarbyl,substituted hydrocarbyl, heterohydrocarbyl, silyl, boryl, phosphino,phosphine, amino, amine, ether, and thioether.

In a preferred embodiment of the invention, each R″ is independentlyhydrogen, or a substituted C₁ to C₁₂ hydrocarbyl group or anunsubstituted C₁ to C₁₂ hydrocarbyl group, preferably R″ is a C₁ to C₂₀substituted or unsubstituted hydrocarbyl, preferably a substituted C₁ toC₁₂ hydrocarbyl group or an unsubstituted C₁ to C₁₂ hydrocarbyl group,preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, or an isomerthereof.

More particular, non-limiting examples of R″ include methyl, ethyl,propyl, butyl, pentyl, hexyl, cyclopentyl, cyclohexyl, benzyl, phenyl,methylphenyl, and tert-butylphenyl groups and the like, including alltheir isomers, for example, tertiary-butyl, isopropyl, and the like.

Preferably R** is a C₃ to C₄ hydrocarbyl (preferably n-propyl orn-butyl).

In a preferred embodiment of the invention, each X is, independently,selected from the group consisting of hydrocarbyl radicals having from 1to 20 carbon atoms, aryls, hydrides, amides, alkoxides, sulfides,phosphides, halides, dienes, amines, phosphines, ethers, and acombination thereof (two X's may form a part of a fused ring or a ringsystem), preferably each X is independently selected from halides, arylsand C₁ to C₅ alkyl groups, preferably each X is a phenyl, methyl, ethyl,propyl, butyl, pentyl, bromo, or chloro group. Preferably, each X is,independently, a halide, a hydride, an alkyl group, an alkenyl group oran arylalkyl group.

Compounds useful as the first metallocene are disclosed in U.S. Pat. No.6,242,545, which is incorporated by reference herein.

In at least one embodiment, the first metallocene catalyst representedby the formula: (A) produces a polyolefin having a high comonomercontent.

Preferably the first metallocene(s) are selected from the groupconsisting of: bis(n-propylcyclopentadienyl)hafnium dichloride,bis(n-propylcyclopentadienyl)hafnium dimethyl,bis(n-propylcyclopentadienyl)zirconium dichloride,bis(n-propylcyclopentadienyl)zirconium dimethyl,bis(n-propylcyclopentadienyl)titanium dichloride,bis(n-propylcyclopentadienyl)titanium dimethyl,(n-propylcyclopentadienyl, pentamethylcyclopentadienyl)zirconiumdichloride, (n-propylcyclopentadienyl,pentamethylcyclopentadienyl)zirconium dimethyl,(n-propylcyclopentadienyl, pentamethylcyclopentadienyl)hafniumdichloride, (n-propylcyclopentadienyl,pentamethylcyclopentadienyl)hafnium dimethyl, (n-propylcyclopentadienyl,pentamethylcyclopentadienyl)titanium dichloride,(n-propylcyclopentadienyl, pentamethylcyclopentadienyl)titaniumdimethyl, (n-propylcyclopentadienyl,tetramethylcyclopentadienyl)zirconium dichloride,(n-propylcyclopentadienyl, tetramethylcyclopentadienyl)zirconiumdimethyl, (n-propylcyclopentadienyl, tetramethylcyclopentadienyl)hafniumdichloride, (n-propylcyclopentadienyl,tetramethylcyclopentadienyl)hafnium dimethyl, (n-propylcyclopentadienyl,tetramethylcyclopentadienyl)titanium dichloride,(n-propylcyclopentadienyl, tetramethylcyclopentadienyl)titaniumdimethyl, bis(cyclopentadienyl)hafnium dimethyl,bis(n-butylcyclopentadienyl)hafnium dichloride,bis(n-butylcyclopentadienyl)hafnium dimethyl,bis(n-butylcyclopentadienyl)zirconium dichloride,bis(n-butylcyclopentadienyl)zirconium dimethyl,bis(n-butylcyclopentadienyl)titanium dichloride,bis(n-butylcyclopentadienyl)titanium dimethyl,bis(1-methyl-3-n-butylcyclopentadienyl)hafnium dichloride,bis(1-methyl-3-n-butylcyclopentadienyl)hafnium dimethyl,bis(1-methyl-3-n-butylcyclopentadienyl)zirconium dichloride,bis(1-methyl-3-n-butylcyclopentadienyl)zirconium dimethyl,bis(1-methyl-3-n-butylcyclopentadienyl)titanium dichloride, andbis(1-methyl-3-n-butylcyclopentadienyl)titanium dimethyl

For purposes of this invention, one catalyst compound is considereddifferent from another if they differ by at least one atom. For example,“bisindenyl zirconium dichloride” is different from“(indenyl)(2-methylindenyl) zirconium dichloride” which is differentfrom “(indenyl)(2-methylindenyl) hafnium dichloride.” Catalyst compoundsthat differ only by isomer are considered the same for purposes if thisinvention, e.g., rac-dimethylsilylbis(2-methyl 4-phenylindenyl)hafniumdimethyl is considered to be the same as meso-dimethylsilylbis(2-methyl4-phenylindenyl)hafnium dimethyl.

Second metallocene catalyst compounds useful herein are compoundsdifferent from compounds represented by formula A and are compoundsrepresented by the formula (B):T _(y) Cp _(m) M ⁶ G _(n) X ⁵ _(q)wherein,each Cp is, independently, a cyclopentadienyl group (such ascyclopentadiene, indene or fluorene) which may be substituted orunsubstituted, provided that at least one Cp is an indene or fluorenegroup;M⁶ is a Group 4 transition metal, for example, titanium, zirconium,hafnium;G is a heteroatom group represented by the formula JR*_(z) where J is N,P, O or S, and R* is a C₁ to C₂₀ hydrocarbyl group and z is 1 or 2;T is a bridging group;y is 0 or 1;X⁵ is a leaving group (such as a halide, a hydride, an alkyl group, analkenyl group or an arylalkyl group);m is 1 or 2;n is 0, 1, 2 or 3;q is 0, 1, 2, or 3; andthe sum of m+n+q is equal to the oxidation state of the transitionmetal, preferably 4. See, for example, WO 2016/094843.

In a preferred embodiment of the invention, each Cp is, independently,an indenyl group which may be substituted or unsubstituted, preferablyeach Cp is independently substituted with a C₁ to C₄₀ hydrocarbyl groupor an unsubstituted C₁ to C₄₀ hydrocarbyl group, preferably Cp is anindenyl group substituted with a C₁ to C₂₀ substituted or unsubstitutedhydrocarbyl, preferably a substituted C₁ to C₁₂ hydrocarbyl group or anunsubstituted C₁ to C₁₂ hydrocarbyl group, preferably methyl, ethyl,propyl, butyl, pentyl, hexyl, or an isomer thereof.

Preferably, T is present (e.g., y=1) and is a bridging group containingat least one Group 13, 14, 15, or 16 element, in particular boron or aGroup 14, 15 or 16 element. Examples of suitable bridging groups includeP(═S)R′, P(═Se)R′, P(═O)R′, R′₂C, R′₂Si, R′₂Ge, R′₂CCR′₂, R′₂CCR′₂CR′₂,R′₂CCR′₂CR′₂CR′₂, R′C═CR′, R′C═CR′CR′₂, R′₂CCR′═CR′CR′₂, R′C═CR′CR′═CR′,R′C═CR′CR′₂CR′₂, R′₂CSiR′₂, R′₂SiSiR′₂, R′₂SiOSiR′₂, R′₂CSiR′₂CR′₂,R′₂SiCR′₂SiR′₂, R′C═CR′SiR′₂, R′₂CGeR′₂, R′₂GeGeR′₂, R′₂CGeR′₂CR′₂,R′₂GeCR′₂GeR′₂, R′₂SiGeR ′₂, R′C═CR′GeR′₂, R′B, R′₂C—BR′, R′₂C—BR′—CR′₂,R′₂C—O—CR′₂, R′₂CR′₂C—O—CR′₂CR′₂, R′₂C—O—CR′₂CR′₂, R′₂C—O—CR′═CR′,R′₂C—S—CR′₂, R′₂CR′₂C—S—CR′₂CR′₂, R′₂C—S—CR′₂CR′₂, R′₂C—S—CR′═CR′,R′₂C—Se—CR′₂, R′₂CR′₂C—Se—CR′₂CR′₂, R′₂C—Se—CR′₂CR′₂, R′₂C—Se—CR′═CR′,R′₂C—N═CR′, R′₂C—NR′—CR′₂, R′₂C—NR′—CR′₂CR′₂, R′₂C—NR′—CR′═CR′,R′₂CR′₂C—NR′—CR′₂CR′₂, R′₂C—P═CR′, R′₂C—PR′—CR′z, O, S, Se, Te, NR′,PR′, AsR′, SbR′, O—O, S—S, R′N—NR′, R′P—PR′, O—S, O—NR′, O—PR′, S—NR′,S—PR′, and R′N—PR′ where R′ is hydrogen or a C₁-C₂₀ containinghydrocarbyl, substituted hydrocarbyl, halocarbyl, substitutedhalocarbyl, silylcarbyl or germylcarbyl substituent and optionally twoor more adjacent R′ may join to form a substituted or unsubstituted,saturated, partially unsaturated or aromatic, cyclic or polycyclicsubstituent. Preferred examples for the bridging group T include CH₂,CH₂CH₂, SiMe₂, SiPh₂, SiMePh, Si(CH₂)₃, Si(CH₂)₄, O, S, NPh, PPh, NMe,PMe, NEt, NPr, NBu, PEt, PPr, Me₂SiOSiMe₂, and PBu.

In a preferred embodiment of the invention in any embodiment of anyformula described herein, T is represented by the formula R^(a) ₂J or(R^(a) ₂J)₂, where J is C, Si, or Ge, and each R^(a) is, independently,hydrogen, halogen, C₁ to C₂₀ hydrocarbyl (such as methyl, ethyl, propyl,butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, or dodecyl)or a C₁ to C₂₀ substituted hydrocarbyl, and two R^(a) can form a cyclicstructure including aromatic, partially saturated, or saturated cyclicor fused ring system. Preferably, T is a bridging group comprisingcarbon or silica, such as dialkylsilyl, preferably T is selected fromCH₂, CH₂CH₂, C(CH₃)₂, SiMe₂, SiPh₂, SiMePh, silylcyclobutyl (Si(CH₂)₃),(Ph)₂C, (p-(Et)₃SiPh)₂C, Me₂SiOSiMe₂, and cyclopentasilylene (Si(CH₂)₄).

In a preferred embodiment of the invention, M⁶ is Zr.

In a preferred embodiment of the invention, G is an alkyl amido group,preferably t-butyl amido or do-decyl amido.

In a preferred embodiment of the invention, each X⁵ is, independently,selected from the group consisting of hydrocarbyl radicals having from 1to 20 carbon atoms, aryls, hydrides, amides, alkoxides, sulfides,phosphides, halides, dienes, amines, phosphines, ethers, and acombination thereof (two X⁵'s may form a part of a fused ring or a ringsystem), preferably each X⁵ is independently selected from halides,aryls and C₁ to C₅ alkyl groups, preferably each X⁵ is a phenyl, methyl,ethyl, propyl, butyl, pentyl, bromo, or chloro group. Preferably, eachX⁵ is, independently, a halide, a hydride, an alkyl group, an alkenylgroup or an arylalkyl group.

In an embodiment, each Cp is independently an indene, which may besubstituted or unsubstituted, each M⁶ is zirconium, and each X⁵ is,independently, a halide, a hydride, an alkyl group, an alkenyl group oran arylalkyl group. In any of the embodiments described herein, y may be1, m may be one, n may be 1, J may be N, and R* may be methyl, ethyl,propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, cyclooctyl,cyclododecyl, decyl, undecyl, dodecyl, adamantyl or an isomer thereof.

In yet another embodiment, the one or more second metallocenepolymerization catalysts may comprise one or more metallocene catalystsof: bis(tetrahydroindenyl)Hf Me₂; (dimethylsilyl)₂O bis(indenyl)ZrCl₂;dimethylsilylbis(tetrahydroindenyl)ZrCl₂;dimethylsilyl-(3-phenyl-indenyl)(tetramethylcyclopentadienyl)ZrCl₂;tetramethyldisilylene bis(4-(3,5-di-tert-butylphenyl)-indenyl)ZrCl₂;bis(indenyl)zirconium dichloride; bis(indenyl)zirconium dimethyl;bis(tetrahydro-1-indenyl)zirconium dichloride;bis(tetrahydro-1-indenyl)zirconium dimethyl;dimethylsilylbis(tetrahydroindenyl)zirconium dichloride;dimethylsilylbis(tetrahydroindenyl)zirconium dimethyl;dimethylsilylbis(indenyl)zirconium dichloride; ordimethylsilyl(bisindenyl)zirconium dimethyl.

In another class of embodiments, the second metallocene catalysts maycomprise bis(indenyl)zirconium dichloride, bis(indenyl)zirconiumdimethyl, bis(tetrahydro-1-indenyl)zirconium dichloride,bis(tetrahydro-1-indenyl)zirconium dimethyl,rac/meso-bis(1-ethylindenyl)zirconium dichloride,rac/meso-bis(1-ethylindenyl)zirconium dimethyl,rac/meso-bis(1-methylindenyl)zirconium dichloride,rac/meso-bis(1-methylindenyl)zirconium dimethyl,rac/meso-bis(1-propylindenyl)zirconium dichloride,rac/meso-bis(1-propylindenyl)zirconium dimethyl,rac/meso-bis(1-butylindenyl)zirconium dichloride,rac/meso-bis(1-butylindenyl)zirconium dimethyl, meso-bis(1 ethylindenyl)zirconium dichloride, meso-bis(1-ethylindenyl) zirconium dimethyl,(1-methylindenyl)(pentamethyl cyclopentadienyl) zirconium dichloride,(1-methylindenyl)(pentamethyl cyclopentadienyl) zirconium dimethyl, orcombinations thereof.

In yet another class of embodiments, the one or more metallocenecatalyst may comprise rac/meso-bis(1-ethylindenyl)zirconium dichloride,rac/meso-bis(1-ethylindenyl)zirconium dimethyl,rac/meso-bis(1-methylindenyl)zirconium dichloride,rac/meso-bis(1-methylindenyl)zirconium dimethyl,rac/meso-bis(1-propylindenyl)zirconium dichloride,rac/meso-bis(1-propylindenyl)zirconium dimethyl,rac/meso-bis(1-butylindenyl)zirconium dichloride,rac/meso-bis(1-butylindenyl)zirconium dimethyl, meso-bis(1-ethylindenyl)zirconium dichloride, meso-bis(1 ethylindenyl) zirconium dimethyl,(1-methylindenyl)(pentamethyl cyclopentadienyl) zirconium dichloride,(1-methylindenyl)(pentamethyl cyclopentadienyl) zirconium dimethyl, orcombinations thereof.

Two or more of the metallocene catalysts as described herein (preferablyat least one catalyst compound represented by formula (A) and at leastone catalyst compound represented by formula (B)) may be used in a mixedcatalyst system also known as a dual catalyst system comprising, forexample, two or three metallocene catalysts or any of the catalystsdescribed herein or known in the art to be useful for olefinpolymerization. They are preferably co-supported, that is disposed onthe same support material, optionally and in addition to, injected intothe reactor(s) separately (with or without a support) or in differentcombinations and proportions together to “trim” or adjust the polymerproduct properties according to its target specification. This approachis very useful in controlling polymer product properties and insuringuniformity in high volume production of polyolefin polymers.

For example, catalyst combinations such as bis(1-ethyl-indenyl)zirconium dimethyl and bis(n-propyl-cyclopentadienyl) hafnium dimethyl,may be used in a catalyst system or a mixed catalyst system, sometimesalso referred to as a dual catalyst system if only two catalysts areused. Particularly preferred catalyst systems comprisebis(1-ethyl-indenyl) zirconium dimethyl, bis(n-propyl-cyclopentadienyl)hafnium dimethyl, a support such as silica, and an activator such as analumoxane (i.e., methylalumoxane).

The two transition metal compounds may be used in any ratio. Preferredmolar ratios of all compounds represented by the formula (A) to allcompounds represented by the formula (B) fall within the range of (A:B)1:1000 to 1000:1, alternatively 1:100 to 500:1, alternatively 1:10 to200:1, alternatively 1:1 to 100:1, and alternatively 1:1 to 75:1, andalternatively 5:1 to 50:1. The particular ratio chosen will depend onthe exact catalysts chosen, the method of activation, and the endproduct desired. In a particular embodiment, when using the twocatalysts, where both are activated with the same activator, useful molepercents, based upon the molecular weight of the pre-catalysts, are 10to 99.9% A to 0.1 to 90% B, alternatively 25 to 99% A to 0.5 to 50% B,alternatively 50 to 99% A to 1 to 25% B, and alternatively 75 to 99% Ato 1 to 10% B.

Activators

The catalyst compositions may be combined with activators in any mannerin the art including by supporting them for use in slurry or gas phasepolymerization. Activators are generally compounds that can activate anyone of the catalyst compounds described above by converting the neutralmetal compound to a catalytically active metal compound cation.Non-limiting activators, for example, include alumoxanes, aluminumalkyls, ionizing activators, which may be neutral or ionic, andconventional-type cocatalysts. Preferred activators typically includealumoxane compounds, modified alumoxane compounds, and ionizing anionprecursor compounds that abstract a reactive, σ-bound, metal ligandmaking the metal compound cationic and providing a charge-balancingnon-coordinating or weakly coordinating anion.

Alumoxane Activators

Alumoxane activators are utilized as activators in the catalystcompositions described herein. Alumoxanes are generally oligomericcompounds containing —Al(R¹)—O-sub-units, where IV is an alkyl group.Examples of alumoxanes include methylalumoxane (MAO), modifiedmethylalumoxane (MMAO), ethylalumoxane and isobutylalumoxane.Alkylalumoxanes and modified alkylalumoxanes are suitable as catalystactivators, particularly when the abstractable ligand is an alkyl,halide, alkoxide or amide. Mixtures of different alumoxanes and modifiedalumoxanes may also be used. It may be preferable to use a visuallyclear methylalumoxane. A cloudy or gelled alumoxane can be filtered toproduce a clear solution or clear alumoxane can be decanted from thecloudy solution. A useful alumoxane is a modified methyl alumoxane(MMAO) cocatalyst type 3A (commercially available from Akzo Chemicals,Inc. under the trade name Modified Methylalumoxane type 3A, coveredunder U.S. Pat. No. 5,041,584).

When the activator is an alumoxane (modified or unmodified), someembodiments select the maximum amount of activator typically at up to a5000-fold molar excess Al/M over the catalyst compound (per metalcatalytic site). The minimum activator-to-catalyst-compound is a 1:1molar ratio. Alternate preferred ranges include from 1:1 to 500:1,alternately from 1:1 to 200:1, alternately from 1:1 to 100:1, oralternately from 1:1 to 50:1.

In a class of embodiments, little or no (zero %) alumoxane is used inthe polymerization processes described herein. Alternatively, thealumoxane is present at a molar ratio of aluminum to catalyst compoundtransition metal less than 500:1, preferably less than 300:1, preferablyless than 100:1, and preferably less than 1:1.

In another class of embodiments, the at least one activator comprisesaluminum and the aluminum to transition metal, for example, hafnium orzirconium, ratio is at least 150 to 1; the at least one activatorcomprises aluminum and the aluminum to transition metal, for example,hafnium or zirconium, ratio is at least 250 to 1; or the at least oneactivator comprises aluminum and the aluminum to transition metal, forexample, hafnium or zirconium, ratio is at least 1,000 to 1.

Ionizing/Non Coordinating Anion Activators

The term “non-coordinating anion” (NCA) means an anion which either doesnot coordinate to a cation or which is only weakly coordinated to acation thereby remaining sufficiently labile to be displaced by aneutral Lewis base. “Compatible” non-coordinating anions are those whichare not degraded to neutrality when the initially formed complexdecomposes. Further, the anion will not transfer an anionic substituentor fragment to the cation so as to cause it to form a neutral transitionmetal compound and a neutral by-product from the anion. Non-coordinatinganions useful in accordance with this invention are those that arecompatible, stabilize the transition metal cation in the sense ofbalancing its ionic charge at +1, and yet retain sufficient lability topermit displacement during polymerization. Ionizing activators usefulherein typically comprise an NCA, particularly a compatible NCA.

It is within the scope of this invention to use an ionizing activator,neutral or ionic, such as tri (n-butyl) ammonium tetrakis(pentafluorophenyl) borate, a tris perfluorophenyl boron metalloidprecursor or a tris perfluoronaphthyl boron metalloid precursor,polyhalogenated heteroborane anions (WO 98/43983), boric acid (U.S. Pat.No. 5,942,459), or combination thereof. It is also within the scope ofthis invention to use neutral or ionic activators alone or incombination with alumoxane or modified alumoxane activators.

For descriptions of useful activators please see U.S. Pat. Nos.8,658,556 and 6,211,105.

Preferred activators include N,N-dimethylaniliniumtetrakis(perfluoronaphthyl)borate, N,N-dimethylaniliniumtetrakis(perfluorobiphenyl)borate, N,N-dimethylaniliniumtetrakis(perfluorophenyl)borate, N,N-dimethylaniliniumtetrakis(3,5-bis(trifluoromethyl)phenyl)borate, triphenylcarbeniumtetrakis(perfluoronaphthyl)borate, triphenylcarbeniumtetrakis(perfluorobiphenyl)borate, triphenylcarbeniumtetrakis(3,5-bis(trifluoromethyl)phenyl)borate, triphenylcarbeniumtetrakis(perfluorophenyl)borate, trimethylammoniumtetrakis(perfluorophenyl)borate;1-(4-(tris(pentafluorophenyl)borate)-2,3,5,6-tetrafluorophenyl)pyrrolidinium;and tetrakis(pentafluorophenyl)borate,4-(tris(pentafluorophenyl)borate)-2,3,5,6-tetrafluoropyridine.

In a preferred embodiment, the activator comprises a triaryl carbonium(such as triphenylcarbenium tetraphenylborate, triphenylcarbeniumtetrakis(pentafluorophenyl)borate, triphenylcarbeniumtetrakis-(2,3,4,6-tetrafluorophenyl)borate, triphenylcarbeniumtetrakis(perfluoronaphthyl)borate, triphenylcarbeniumtetrakis(perfluorobiphenyl)borate, triphenylcarbeniumtetrakis(3,5-bis(trifluoromethyl)phenyl)borate).

In another embodiment, the activator comprises one or more oftrialkylammonium tetrakis(pentafluorophenyl)borate, N,N-dialkylaniliniumtetrakis(pentafluorophenyl)borate,N,N-dimethyl-(2,4,6-trimethylanilinium)tetrakis(pentafluorophenyl)borate, trialkylammoniumtetrakis-(2,3,4,6-tetrafluorophenyl) borate, N,N-dialkylaniliniumtetrakis-(2,3,4,6-tetrafluorophenyl)borate, trialkylammoniumtetrakis(perfluoronaphthyl)borate, N,N-dialkylaniliniumtetrakis(perfluoronaphthyl)borate, trialkylammoniumtetrakis(perfluorobiphenyl)borate, N,N-dialkylaniliniumtetrakis(perfluorobiphenyl)borate, trialkylammoniumtetrakis(3,5-bis(trifluoromethyl)phenyl)borate, N,N-dialkylaniliniumtetrakis(3,5-bis(trifluoromethyl)phenyl)borate,N,N-dialkyl-(2,4,6-trimethylanilinium)tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, di-(i-propyl)ammoniumtetrakis(pentafluorophenyl)borate, (where alkyl is methyl, ethyl,propyl, n-butyl, sec-butyl, or t-butyl).

The typical activator-to-catalyst ratio, e.g., all NCAactivators-to-catalyst ratio is about a 1:1 molar ratio. Alternatepreferred ranges include from 0.1:1 to 100:1, alternately from 0.5:1 to200:1, alternately from 1:1 to 500:1 alternately from 1:1 to 1000:1. Aparticularly useful range is from 0.5:1 to 10:1, preferably 1:1 to 5:1.

Support Materials

The catalyst composition comprises at least one “support” or sometimesalso referred to as a “carrier”. The terms may be interchangeable unlessotherwise distinguished. Suitable supports, include but are not limitedto silica, alumina, silica-alumina, zirconia, titania, silica-alumina,cerium oxide, magnesium oxide, or combinations thereof. The catalyst mayoptionally comprise a support or be disposed on at least one support.Suitable supports, include but are not limited to, active and inactivematerials, synthetic or naturally occurring zeolites, as well asinorganic materials such as clays and/or oxides such as silica, alumina,zirconia, titania, silica-alumina, cerium oxide, magnesium oxide, orcombinations thereof. In particular, the support may be silica-alumina,alumina and/or a zeolite, particularly alumina. Silica-alumina may beeither naturally occurring or in the form of gelatinous precipitates orgels including mixtures of silica and metal oxides.

In class of embodiments, the at least one support may comprise anorganosilica material. The organosilica material supports may be apolymer formed of at least one monomer. In certain embodiments, theorganosilica material may be a polymer formed of multiple distinctmonomers. Methods and materials for producing the organosilica materialsas well as a characterization description may be found in, for example,WO 2016/094770 and WO 2016 094774.

Preferably, the support material is an inorganic oxide in a finelydivided form. Suitable inorganic oxide materials for use in catalystsystems herein include Groups 2, 4, 13, and 14 metal oxides, such assilica, alumina, and mixtures thereof. Other inorganic oxides that maybe employed either alone or in combination with the silica, or aluminaare magnesia, titania, zirconia, and the like. Other suitable supportmaterials, however, can be employed, for example, finely dividedfunctionalized polyolefins, such as finely divided polyethylene.Particularly useful supports include magnesia, titania, zirconia,montmorillonite, phyllosilicate, zeolites, talc, clays, and the like.Also, combinations of these support materials may be used, for example,silica-chromium, silica-alumina, silica-titania, and the like. Preferredsupport materials include Al₂O₃, ZrO₂, SiO₂, and combinations thereof,more preferably SiO₂, Al₂O₃, or SiO₂/Al₂O₃.

Scavengers, Chain Transfer Agents and/or Co-Activators

Scavengers, chain transfer agents, or co-activators may also be used.Aluminum alkyl compounds which may be utilized as scavengers orco-activators include, for example, one or more of those represented bythe formula AlR₃, where each R is, independently, a C₁-C₈ aliphaticradical, preferably methyl, ethyl, propyl, butyl, pentyl, hexyl octyl oran isomer thereof), especially trimethylaluminum, triethylaluminum,triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum ormixtures thereof.

Useful chain transfer agents that may also be used herein are typicallya compound represented by the formula AlR²⁰ ₃, ZnR²⁰ ₂ (where each R²⁰is, independently, a C₁-C₈ aliphatic radical, preferably methyl, ethyl,propyl, butyl, pentyl, hexyl octyl or an isomer thereof) or acombination thereof, such as diethyl zinc, trimethylaluminum,triisobutylaluminum, trioctylaluminum, or a combination thereof.

Polymerization Processes

In embodiments herein, the invention relates to polymerization processeswhere monomer (such as propylene and or ethylene), and optionallycomonomer, are contacted with a catalyst system comprising at least oneactivator, at least one support and at least two catalyst compounds,such as the metallocene compounds described above. The support, catalystcompounds, and activator may be combined in any order, and are combinedtypically prior to contacting with the monomers.

Monomers useful herein include substituted or unsubstituted C₂ to C₄₀alpha olefins, preferably C₂ to C₂₀ alpha olefins, preferably C₂ to C₁₂alpha olefins, preferably ethylene, propylene, butene, pentene, hexene,heptene, octene, nonene, decene, undecene, dodecene and isomers thereof.

In an embodiment of the invention, the monomer comprises propylene andan optional comonomers comprising one or more ethylene or C₄ to C₄₀olefins, preferably C₄ to C₂₀ olefins, or preferably C₆ to C₁₂ olefins.The C₄ to C₄₀ olefin monomers may be linear, branched, or cyclic. The C₄to C₄₀ cyclic olefins may be strained or unstrained, monocyclic orpolycyclic, and may optionally include heteroatoms and/or one or morefunctional groups.

In another embodiment of the invention, the monomer comprises ethyleneand optional comonomers comprising one or more C₃ to C₄₀ olefins,preferably C₄ to C₂₀ olefins, or preferably C₆ to C₁₂ olefins. The C₃ toC₄₀ olefin monomers may be linear, branched, or cyclic. The C₃ to C₄₀cyclic olefins may be strained or unstrained, monocyclic or polycyclic,and may optionally include heteroatoms and/or one or more functionalgroups.

Exemplary C₂ to C₄₀ olefin monomers and optional comonomers includeethylene, propylene, butene, pentene, hexene, heptene, octene, nonene,decene, undecene, dodecene, norbornene, norbornadiene,dicyclopentadiene, cyclopentene, cycloheptene, cyclooctene,cyclooctadiene, cyclododecene, 7-oxanorbornene, 7-oxanorbornadiene,substituted derivatives thereof, and isomers thereof, preferably hexene,heptene, octene, nonene, decene, dodecene, cyclooctene,1,5-cyclooctadiene, 1-hydroxy-4-cyclooctene, 1-acetoxy-4-cyclooctene,5-methylcyclopentene, cyclopentene, dicyclopentadiene, norbornene,norbornadiene, and their respective homologs and derivatives, preferablynorbornene, norbornadiene, and dicyclopentadiene.

In a preferred embodiment one or more dienes are present in the polymerproduced herein at up to 10 wt %, preferably at 0.00001 to 1.0 wt %,preferably 0.002 to 0.5 wt %, even more preferably 0.003 to 0.2 wt %,based upon the total weight of the composition. In some embodiments 500ppm or less of diene is added to the polymerization, preferably 400 ppmor less, preferably or 300 ppm or less. In other embodiments at least 50ppm of diene is added to the polymerization, or 100 ppm or more, or 150ppm or more.

Diolefin monomers useful in this invention include any hydrocarbonstructure, preferably C₄ to C₃₀, having at least two unsaturated bonds,wherein at least two of the unsaturated bonds are readily incorporatedinto a polymer by either a stereospecific or a non-stereospecificcatalyst(s). It is further preferred that the diolefin monomers beselected from alpha, omega-diene monomers (i.e., di-vinyl monomers).More preferably, the diolefin monomers are linear di-vinyl monomers,most preferably those containing from 4 to 30 carbon atoms. Examples ofpreferred dienes include butadiene, pentadiene, hexadiene, heptadiene,octadiene, nonadiene, decadiene, undecadiene, dodecadiene, tridecadiene,tetradecadiene, pentadecadiene, hexadecadiene, heptadecadiene,octadecadiene, nonadecadiene, icosadiene, heneicosadiene, docosadiene,tricosadiene, tetracosadiene, pentacosadiene, hexacosadiene,heptacosadiene, octacosadiene, nonacosadiene, triacontadiene,particularly preferred dienes include 1,6-heptadiene, 1,7-octadiene,1,8-nonadiene, 1,9-decadiene, 1,10-undecadiene, 1,11-dodecadiene,1,12-tridecadiene, 1,13-tetradecadiene, and low molecular weightpolybutadienes (M_(w) less than 1000 g/mol). Preferred cyclic dienesinclude cyclopentadiene, vinylnorbornene, norbornadiene, ethylidenenorbornene, divinylbenzene, dicyclopentadiene or higher ring containingdiolefins with or without substituents at various ring positions.

Polymerization processes according to the present disclosure can becarried out in any manner known in the art. Any suspension, slurry, highpressure tubular or autoclave process, or gas phase polymerizationprocess known in the art can be used under polymerizable conditions.Such processes can be run in a batch, semi-batch, or continuous mode.Heterogeneous polymerization processes (such as gas phase and slurryphase processes) are useful. A heterogeneous process is defined to be aprocess where the catalyst system is not soluble in the reaction media.Alternatively, in other embodiments, the polymerization process is nothomogeneous.

A homogeneous polymerization process is defined to be a process wherepreferably at least 90 wt % of the product is soluble in the reactionmedia. Alternatively, the polymerization process is not a bulk process.In a class of embodiments, a bulk process is defined to be a processwhere monomer concentration in all feeds to the reactor is preferably 70vol % or more. Alternatively, no solvent or diluent is present or addedin the reaction medium, (except for the small amounts used as thecarrier for the catalyst system or other additives, or amounts typicallyfound with the monomer; e.g., propane in propylene). In anotherembodiment, the process is a slurry process. As used herein the term“slurry polymerization process” means a polymerization process where asupported catalyst is employed and monomers are polymerized on thesupported catalyst particles. At least 95 wt % of polymer productsderived from the supported catalyst are in granular form as solidparticles (not dissolved in the diluent).

Suitable diluents/solvents for polymerization include non-coordinating,inert liquids. Examples include straight and branched-chainhydrocarbons, such as isobutane, butane, pentane, isopentane, hexanes,isohexane, heptane, octane, dodecane, and mixtures thereof; cyclic andalicyclic hydrocarbons, such as cyclohexane, cycloheptane,methylcyclohexane, methylcycloheptane, and mixtures thereof, such as canbe found commercially (Isopar™); perhalogenated hydrocarbons, such asperfluorinated C₄₋₁₀ alkanes, chlorobenzene, and aromatic andalkylsubstituted aromatic compounds, such as benzene, toluene,mesitylene, and xylene. Suitable solvents also include liquid olefinswhich may act as monomers or comonomers including ethylene, propylene,1-butene, 1-hexene, 1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene,1-octene, 1-decene, and mixtures thereof. In a preferred embodiment,aliphatic hydrocarbon solvents are used as the solvent, such asisobutane, butane, pentane, isopentane, hexanes, isohexane, heptane,octane, dodecane, and mixtures thereof; cyclic and alicyclichydrocarbons, such as cyclohexane, cycloheptane, methylcyclohexane,methylcycloheptane, and mixtures thereof. In another embodiment, thesolvent is not aromatic, preferably aromatics are present in the solventat less than 1 wt %, preferably less than 0.5 wt %, preferably less than0 wt % based upon the weight of the solvents.

In a preferred embodiment, the feed concentration of the monomers andcomonomers for the polymerization is 60 vol % solvent or less,preferably 40 vol % or less, or preferably 20 vol % or less, based onthe total volume of the feedstream. Preferably the polymerization is runin a bulk process.

Preferred polymerizations can be run at any temperature and/or pressuresuitable to obtain the desired ethylene polymers and as described above.Typical pressures include pressures in the range of from about 0.35 MPato about 10 MPa, preferably from about 0.45 MPa to about 6 MPa, orpreferably from about 0.5 MPa to about 4 MPa in some embodiments.

In some embodiments, hydrogen is present in the polymerization reactorat a partial pressure of 0.001 to 50 psig (0.007 to 345 kPa), preferablyfrom 0.01 to 25 psig (0.07 to 172 kPa), more preferably 0.1 to 10 psig(0.7 to 70 kPa).

In a class of embodiments, the polymerization is performed in the gasphase, preferably, in a fluidized bed gas phase process. Generally, in afluidized bed gas phase process used for producing polymers, a gaseousstream containing one or more monomers is continuously cycled through afluidized bed in the presence of a catalyst under reactive conditions.The gaseous stream is withdrawn from the fluidized bed and recycled backinto the reactor. Simultaneously, polymer product is withdrawn from thereactor and fresh monomer is added to replace the polymerized monomer.(See, for example, U.S. Pat. Nos. 4,543,399; 4,588,790; 5,028,670;5,317,036; 5,352,749; 5,405,922; 5,436,304; 5,453,471; 5,462,999;5,616,661; and 5,668,228; all of which are fully incorporated herein byreference.)

In another embodiment of the invention, the polymerization is performedin the slurry phase. A slurry polymerization process generally operatesbetween 1 to about 50 atmosphere pressure range (15 psi to 735 psi, 103kPa to 5068 kPa) or even greater and temperatures as described above. Ina slurry polymerization, a suspension of solid, particulate polymer isformed in a liquid polymerization diluent medium to which monomer andcomonomers, along with catalysts, are added. The suspension includingdiluent is intermittently or continuously removed from the reactor wherethe volatile components are separated from the polymer and recycled,optionally after a distillation, to the reactor. The liquid diluentemployed in the polymerization medium is typically an alkane having from3 to 7 carbon atoms, preferably a branched alkane. The medium employedshould be liquid under the conditions of polymerization and relativelyinert. When a propane medium is used, the process is typically operatedabove the reaction diluent critical temperature and pressure. Often, ahexane or an isobutane medium is employed.

In an embodiment, a preferred polymerization technique useful in theinvention is referred to as a particle form polymerization, or a slurryprocess where the temperature is kept below the temperature at which thepolymer goes into solution. Such technique is known in the art, anddescribed in for instance U.S. Pat. No. 3,248,179. A preferredtemperature in the particle form process is within the range of about85° C. to about 110° C. Two preferred polymerization methods for theslurry process are those employing a loop reactor and those utilizing aplurality of stirred reactors in series, parallel, or combinationsthereof. Non-limiting examples of slurry processes include continuousloop or stirred tank processes. Also, other examples of slurry processesare described in U.S. Pat. No. 4,613,484, which is herein fullyincorporated by reference.

In another embodiment, the slurry process is carried out continuously ina loop reactor. The catalyst, as a slurry in isobutane or as a dry freeflowing powder, is injected regularly to the reactor loop, which isitself filled with circulating slurry of growing polymer particles in adiluent of isobutane containing monomer and comonomer. Hydrogen,optionally, may be added as a molecular weight control. In oneembodiment 500 ppm or less of hydrogen is added, or 400 ppm or less or300 ppm or less. In other embodiments at least 50 ppm of hydrogen isadded, or 100 ppm or more, or 150 ppm or more.

Reaction heat is removed through the loop wall since much of the reactoris in the form of a double-jacketed pipe. The slurry is allowed to exitthe reactor at regular intervals or continuously to a heated lowpressure flash vessel, rotary dryer and a nitrogen purge column insequence for removal of the isobutane diluent and all unreacted monomerand comonomers. The resulting hydrocarbon free powder is then compoundedfor use in various applications.

In a preferred embodiment, the catalyst system used in thepolymerization comprises no more than two catalyst compounds. A“reaction zone” also referred to as a “polymerization zone” is a vesselwhere polymerization takes place, for example a batch reactor. Whenmultiple reactors are used in either series or parallel configuration,each reactor is considered as a separate polymerization zone. For amulti-stage polymerization in both a batch reactor and a continuousreactor, each polymerization stage is considered as a separatepolymerization zone. In a preferred embodiment, the polymerizationoccurs in one reaction zone.

Useful reactor types and/or processes for the production of polyolefinpolymers include, but are not limited to, UNIPOL™ Gas Phase Reactors(available from Univation Technologies); INEOS™ Gas Phase Reactors andProcesses; Continuous Flow Stirred-Tank (CSTR) reactors (solution andslurry); Plug Flow Tubular reactors (solution and slurry); Slurry:(e.g., Slurry Loop (single or double loops)) (available from ChevronPhillips Chemical Company) and (Series Reactors) (available from MitsuiChemicals)); BORSTAR™ Process and Reactors (slurry combined with gasphase); and Multi-Zone Circulating Reactors (MzCR) such as SPHERIZONE™Reactors and Process available from Lyondell Basell.

In several classes of embodiments, the catalyst activity of thepolymerization reaction is at least 4,250 g/g*cat or greater, at least4,750 g/g*cat or greater, at least 5,000 g/g*cat or greater, at least6,250 g/g*cat or greater, at least 8,500 g/g*cat or greater, at least9,000 g/g*cat or greater, at least 9,500 g/g*cat or greater, or at least9,700 g/g*cat or greater.

In a preferred embodiment, the polymerization:

1) is conducted at temperatures of 0 to 300° C. (preferably 25 to 150°C., preferably 40 to 120° C., preferably 45 to 80° C.);

2) is conducted at a pressure of atmospheric pressure to 10 MPa(preferably 0.35 to 10 MPa, preferably from 0.45 to 6 MPa, preferablyfrom 0.5 to 4 MPa);

3) is conducted in an aliphatic hydrocarbon solvent (such as isobutane,butane, pentane, isopentane, hexane, isohexane, heptane, octane,dodecane, and mixtures thereof; cyclic and alicyclic hydrocarbons, suchas cyclohexane, cycloheptane, methylcyclohexane, methylcycloheptane, andmixtures thereof; preferably where aromatics are preferably present inthe solvent at less than 1 wt %, preferably less than 0.5 wt %,preferably at 0 wt % based upon the weight of the solvents);

4) wherein the catalyst system used in the polymerization preferablycomprises bis(1-ethyl-indenyl) zirconium dimethyl,bis(n-propyl-cyclopentadienyl) hafnium dimethyl, a support such assilica, and an activator (such as methylalumoxane, N,N-dimethylaniliniumtetrakis(pentafluorophenyl)borate, or N,N-dimethylaniliniumtetrakis(perfluoronaphthyl)borate);

5) the polymerization preferably occurs in one reaction zone;

6) the productivity of the catalyst compound is at least 4,250 g/g*cator greater, at least 4,750 g/g*cat or greater, at least 5,000 g/g*cat orgreater, at least 6,250 g/g*cat or greater, at least 8,500 g/g*cat orgreater, at least 9,000 g/g*cat or greater, at least 9,500 g/g*cat orgreater, or at least 9,700 g/g*cat or greater;

7) optionally scavengers (such as trialkyl aluminum compounds) areabsent (e.g. present at zero mol %, alternately the scavenger is presentat a molar ratio of scavenger metal to transition metal of less than100:1, preferably less than 50:1, preferably less than 15:1, preferablyless than 10:1); and

8) optionally hydrogen is present in the polymerization reactor at apartial pressure of 0.001 to 50 psig (0.007 to 345 kPa) (preferably from0.01 to 25 psig (0.07 to 172 kPa), more preferably 0.1 to 10 psig (0.7to 70 kPa)).

Polyolefin Products

In an embodiment, the process described herein produces polyethylenecompositions including homopolymers and copolymers of one, two, three,four or more C₂ to C₄₀ olefin monomers, for example, C₂ to C₂₀ α-olefinmonomers.

For example, the polyethylene compositions include copolymers of a C₂ toC₄₀ olefin and one, two or three or more different C₂ to C₄₀ olefins,(where the C₂ to C₄₀ olefins are preferably C₃ to C₂₀ olefins,preferably are C₃ to C₁₂ α-olefin, preferably are propylene, butene,hexene, octene, decene, dodecene, preferably propylene, butene, hexene,octene, or a mixture thereof).

The polyethylene composition may comprise from 99.0 to about 80.0 wt %,99.0 to 85.0 wt %, 99.0 to 87.5 wt %, 99.0 to 90.0 wt %, 99.0 to 92.5 wt%, 99.0 to 95.0 wt %, or 99.0 to 97.0 wt %, of polymer units derivedfrom ethylene and about 1.0 to about 20.0 wt %, 1.0 to 15.0 wt %, 0.5 to12.5 wt %, 1.0 to 10.0 wt %, 1.0 to 7.5 wt %, 1.0 to 5.0 wt %, or 1.0 to3.0 wt % of polymer units derived from one or more C₃ to C₂₀ α-olefincomonomers, preferably C₃ to C₁₀ α-olefins, and more preferably C₄ to C₈α-olefins, such as hexene and octene. The α-olefin comonomer may belinear or branched, and two or more comonomers may be used, if desired.

Examples of suitable comonomers include propylene, butene, 1-pentene;1-pentene with one or more methyl, ethyl, or propyl substituents;1-hexene; 1-hexene with one or more methyl, ethyl, or propylsubstituents; 1-heptene; 1-heptene with one or more methyl, ethyl, orpropyl substituents; 1-octene; 1-octene with one or more methyl, ethyl,or propyl substituents; 1-nonene; 1-nonene with one or more methyl,ethyl, or propyl substituents; ethyl, methyl, or dimethyl-substituted1-decene; 1-dodecene; and styrene. Particularly suitable comonomersinclude 1-butene, 1-hexene, and 1-octene, 1-hexene, and mixturesthereof.

The polyethylene composition may have a melt index, I_(2.16), accordingto the test method listed below, of ≥about 0.10 g/10 min, e.g., ≥about0.15 g/10 min, ≥about 0.18 g/10 min, ≥about 0.20 g/10 min, ≥about 0.22g/10 min, ≥about 0.25 g/10 min, ≥about 0.28 g/10 min, or ≥about 0.30g/10 min and, also, a melt index (I_(2.16))≤about 3.00 g/10 min, e.g.,≤about 2.00 g/10 min, ≤about 1.00 g/10 min, ≤about 0.70 g/10 min, ≤about0.50 g/10 min, ≤about 0.40 g/10 min, or ≤about 0.30 g/10 min. Rangesexpressly disclosed include, but are not limited to, ranges formed bycombinations any of the above-enumerated values, e.g., about 0.10 toabout 0.30, about 0.15 to about 0.25, about 0.18 to about 0.22 g/10 min,etc. In another embodiment, the melt index could be about 0.1 g/10 minto about 30 g/10 min, such as about 20 g/10 min to about 30 g/10 min.

The polyethylene composition may have a high load melt index (HLMI)(I_(21.6)) in accordance with the test method listed below of from 1 to60 g/10 min, 5 to 40 g/10 min, 5 to 50 g/10 min, 15 to 50 g/10 min, or20 to 50 g/10 min.

The polyethylene composition may have a melt index ratio (MIR), from 10to 90, from 20 to 45, from 25 to 60, alternatively, from 30 to 55,alternatively, from 35 to 55, and alternatively, from 35 to 50 or 35 to45. MIR is defined as I_(21.6)/I_(2.16).

The polyethylene composition may have a density of about 0.920 g/cm³,about 0.918 g/cm³, or ≥about 0.910 g/cm³, e.g., ≥about 0.919 g/cm³,≥about 0.92 g/cm³, ≥about 0.930 g/cm³, ≥about 0.932 g/cm³. Additionally,the polyethylene composition may have a density ≤about 0.945 g/cm³,e.g., ≤about 0.940 g/cm³, ≤about 0.937 g/cm³, ≤about 0.935 g/cm³, ≤about0.933 g/cm³, or ≤about 0.930 g/cm³. Ranges expressly disclosed include,but are not limited to, ranges formed by combinations any of theabove-enumerated values, e.g., about 0.919 to about 0.945 g/cm³, 0.920to 0.930 g/cm³, 0.925 to 0.935 g/cm³, 0.920 to 0.940 g/cm³, etc. Densityis determined in accordance with the test method listed below.

The polyethylene composition may have a molecular weight distribution(MwD, defined as M_(w)/M_(n)) of about 2 to about 12, about 5 to about10.5 or 11, about 2.5 to about 5.5, preferably 4.0 to 5.0 and about 4.4to 5.0.

In a class of embodiments, the polyethylene composition comprises atleast 65 wt % ethylene derived units and from 0 to 35 wt % of C₃-C₁₂olefin comonomer derived units, based upon the total weight of thepolyethylene composition; wherein the polyethylene composition has:

-   -   a) an RCI,m of 100 kg/mol or greater, alternatively, 110 kg/mol        or greater, alternatively, 125 kg/mol or greater, alternatively,        150 kg/mol or greater, alternatively, 170 kg/mol or greater, and        alternatively, 185 kg/mol or greater;

and one or both of:

-   -   b) a Tw₁-Tw₂ value of from −16 to −38° C., alternatively, a        Tw₁-Tw₂ value of from −23 to −36° C., and alternatively, a        Tw₁-Tw₂ value of from −23 to −33° C.; and    -   c) an Mw₁/Mw₂ value of at least 0.9, alternatively, an Mw₁/Mw₂        value of from 0.9 to 4, and alternatively, an Mw₁/Mw₂ value of        from 1.25 to 4;        and one or more of the following:    -   d) a density of from 0.890 g/cm³ to 0.940 g/cm³;    -   e) a melt index (MI) of from 0.1 g/10 min to 30 g/10 min,        alternatively, a melt index (MI) of from 0.1 g/10 min to 6 g/10        min;    -   f) a melt index ratio (I₂₁/I₂) of from 10 to 90;    -   g) an M_(w)/M_(n) of from 2 to 12;    -   h) an M_(z)/M_(w) of from 2.5 to 5.0;    -   i) an M_(z)/M_(n) of from 10 to 40; and    -   j) a g′(vis) of 0.900 or greater, alternatively, 0.930 or        greater, alternatively, 0.940 or greater, and alternatively        0.994 or greater.

This invention also relates to polyethylene compositions comprising atleast 65 wt % ethylene derived units and from 0 to 35 wt % of C₃-C₁₂olefin comonomer derived units, based upon the total weight of thepolyethylene composition; wherein the polyethylene composition has:

-   -   a) an RCI,m of 100 kg/mol or greater, such as 150 kg/mol or        greater;        and one or both of:    -   b) a Tw₁-Tw₂ value of from −16 to −38° C.; and    -   c) an Mw₁/Mw₂ value of at least 0.9, such as at least 2 or at        least 3;        and one or more of the following:    -   d) a density of from 0.890 g/cm³ to 0.940 g/cm³;    -   e) a melt index (MI) of from 0.1 g/10 min to 30 g/10 min;    -   f) a melt index ratio (I₂₁/I₂) of from 10 to 90, such 30 to 55,        or 35 to 45;    -   g) an M_(w)/M_(n) of from 2 to 16, such as 9 to 14, or 10 to 14;    -   h) an M_(z)/M_(w) of from 2.5 to 5.0;    -   i) an M_(z)/M_(n) of from 10 to 50, such as 25 to 50, or 25 to        45; and    -   j) a g′(vis) of 0.900 or greater.

In any of the embodiments described herein, the polyethylene compositionmay be a multimodal polyethylene composition such as a bimodalpolyethylene composition. As used herein, “multimodal” means that thereare at least two distinguishable peaks in a molecular weightdistribution curve (as determined using gel permeation chromatography(GPC) or other recognized analytical technique) of a polyethylenecomposition. For example, if there are two distinguishable peaks in themolecular weight distribution curve such composition may be referred toas bimodal composition. Typically, if there is only one peak (e.g.,monomodal), no obvious valley between the peaks, either one of the peaksis not considered as a distinguishable peak, or both peaks are notconsidered as distinguishable peaks, then such a composition may bereferred to as non-bimodal. For example, in U.S. Pat. Nos. 8,846,841 and8,691,715, FIGS. 1-5 illustrate representative bimodal molecular weightdistribution curves. In these figures, there is a valley between thepeaks, and the peaks can be separated or deconvoluted. Often, a bimodalmolecular weight distribution is characterized as having an identifiablehigh molecular weight component (or distribution) and an identifiablelow molecular weight component (or distribution). In contrast, in U.S.Pat. Nos. 8,846,841 and 8,691,715, FIGS. 6-11 illustrate representativenon-bimodal molecular weight distribution curves. These include unimodalmolecular weight distributions as well as distribution curves containingtwo peaks that cannot be easily distinguished, separated, ordeconvoluted.

In any of the embodiments described herein, the polyethylene compositionmay have an internal unsaturation as measured by ¹H NMR (see below forthe test method) of more than 0.2 total internal unsaturations perthousand carbon atoms, alternatively, more than 0.3 total internalunsaturations per thousand carbon atoms, alternatively, more than 0.32total internal unsaturations per thousand carbon atoms, alternatively,more than 0.38 total internal unsaturations per thousand carbon atoms,and alternatively, more than 0.4 total internal unsaturations perthousand carbon atoms.

Blends

In another embodiment, the polymer (preferably the polyethylene orpolypropylene) or polyethylene composition produced herein is combinedwith one or more additional polymers in a blend prior to being formedinto a film, molded part, or other article. As used herein, a “blend”may refer to a dry or extruder blend of two or more different polymers,and in-reactor blends, including blends arising from the use of multi ormixed catalyst systems in a single reactor zone, and blends that resultfrom the use of one or more catalysts in one or more reactors under thesame or different conditions (e.g., a blend resulting from in seriesreactors (the same or different) each running under different conditionsand/or with different catalysts).

Useful additional polymers include other polyethylenes, isotacticpolypropylene, highly isotactic polypropylene, syndiotacticpolypropylene, random copolymer of propylene and ethylene, and/orbutene, and/or hexene, polybutene, ethylene vinyl acetate, LDPE, LLDPE,HDPE, ethylene vinyl acetate, ethylene methyl acrylate, copolymers ofacrylic acid, polymethylmethacrylate or any other polymers polymerizableby a high-pressure free radical process, polyvinylchloride,polybutene-1, isotactic polybutene, ABS resins, ethylene-propylenerubber (EPR), vulcanized EPR, EPDM, block copolymer, styrenic blockcopolymers, polyamides, polycarbonates, PET resins, cross linkedpolyethylene, copolymers of ethylene and vinyl alcohol (EVOH), polymersof aromatic monomers such as polystyrene, poly-1 esters, polyacetal,polyvinylidine fluoride, polyethylene glycols, and/or polyisobutylene.

End Uses

Any of the foregoing polymers and compositions in combination withoptional additives (see, for example, U.S. Patent Publication No.2016/0060430, paragraphs [0082]-[0093]) may be used in a variety ofend-use applications. Such end uses may be produced by methods known inthe art. End uses include polymer products and products having specificend-uses. Exemplary end uses are films, film-based products, diaperbacksheets, housewrap, wire and cable coating compositions, articlesformed by molding techniques, e.g., injection or blow molding, extrusioncoating, foaming, casting, and combinations thereof. End uses alsoinclude products made from films, e.g., bags, packaging, and personalcare films, pouches, medical products, such as for example, medicalfilms and intravenous (IV) bags.

Films

Films include monolayer or multilayer films. Films include those filmstructures and film applications known to those skilled in the art.Specific end use films include, for example, blown films, cast films,stretch films, stretch/cast films, stretch cling films, stretch handwrapfilms, machine stretch wrap, shrink films, shrink wrap films, greenhouse films, laminates, and laminate films. Exemplary films are preparedby any conventional technique known to those skilled in the art, such asfor example, techniques utilized to prepare blown, extruded, and/or caststretch and/or shrink films (including shrink-on-shrink applications).

In one embodiment, multilayer films or multiple-layer films may beformed by methods well known in the art. The total thickness ofmultilayer films may vary based upon the application desired. A totalfilm thickness of about 5-100 μm, more typically about 10-50 μm, issuitable for most applications. Those skilled in the art will appreciatethat the thickness of individual layers for multilayer films may beadjusted based on desired end-use performance, resin or copolymeremployed, equipment capability, and other factors. The materials formingeach layer may be coextruded through a coextrusion feedblock and dieassembly to yield a film with two or more layers adhered together butdiffering in composition. Coextrusion can be adapted for use in bothcast film or blown film processes. Exemplary multilayer films have atleast two, at least three, or at least four layers. In one embodimentthe multilayer films are composed of five to ten layers.

To facilitate discussion of different film structures, the followingnotation is used herein. Each layer of a film is denoted “A” or “B”.Where a film includes more than one A layer or more than one B layer,one or more prime symbols (′, ″, ′″, etc.) are appended to the A or Bsymbol to indicate layers of the same type that can be the same or candiffer in one or more properties, such as chemical composition, density,melt index, thickness, etc. Finally, the symbols for adjacent layers areseparated by a slash (/). Using this notation, a three-layer film havingan inner layer disposed between two outer layers would be denotedA/B/A′. Similarly, a five-layer film of alternating layers would bedenoted AB/A′/B′/A″. Unless otherwise indicated, the left-to-right orright-to-left order of layers does not matter, nor does the order ofprime symbols; e.g., an A/B film is equivalent to a B/A film, and anA/A′/B/A″ film is equivalent to an A/B/A′/A″ film, for purposesdescribed herein. The relative thickness of each film layer is similarlydenoted, with the thickness of each layer relative to a total filmthickness of 100 (dimensionless) indicated numerically and separated byslashes; e.g., the relative thickness of an A/B/A′ film having A and A′layers of 10 μm each and a B layer of 30 μm is denoted as 20/60/20.

The thickness of each layer of the film, and of the overall film, is notparticularly limited, but is determined according to the desiredproperties of the film. Typical film layers have a thickness of fromabout 1 to about 1000 μm, more typically from about 5 to about 100 μm,and typical films have an overall thickness of from about 10 to about100 μm.

In some embodiments, and using the nomenclature described above, thepresent invention provides for multilayer films with any of thefollowing exemplary structures: (a) two-layer films, such as A/B andB/B′; (b) three-layer films, such as A/B/A′, A/A′/B, B/A/B′ and B/B′/B″;(c) four-layer films, such as A/A′/A″/B, A/A′/B/A″, A/A′/B/B′,A/B/A′/B′, A/B/B′/A′, B/A/A′/B′, A/B/B′/B″, B/A/B′/B″ and B/B′/B″/B′″;(d) five-layer films, such as A/A′/A″/A′″/B, A/A′/A″/B/A′″,A/A′/B/A″/A′″, A/A′/A″/B/B′, A/A′/B/A″/B′, A/A′/B/B′/A″, A/B/A′/B′/A″,A/B/A′/A″/B, B/A/A′/A″/B′, A/A′/B/B′/B″, A/B/A′/B′/B″, A/B/B′/B″/A′,B/A/A′/B′/B″, B/A/B′/A′/B″, B/A/B′/B″/A′, A/B/B′/B″/B′″, B/A/B′/B″/B′″,B/B′/A/B″/B′″, and B/B′/B″/B′″/B″″; and similar structures for filmshaving six, seven, eight, nine, twenty-four, forty-eight, sixty-four,one hundred, or any other number of layers. It should be appreciatedthat films having still more layers.

In any of the embodiments above, one or more A layers can be replacedwith a substrate layer, such as glass, plastic, paper, metal, etc., orthe entire film can be coated or laminated onto a substrate. Thus,although the discussion herein has focused on multilayer films, thefilms may also be used as coatings for substrates such as paper, metal,glass, plastic, and other materials capable of accepting a coating.

The films can further be embossed, or produced or processed according toother known film processes. The films can be tailored to specificapplications by adjusting the thickness, materials and order of thevarious layers, as well as the additives in or modifiers applied to eachlayer.

Preferably, the articles (preferably films) produced herein have anaverage MD/TD modulus ((MD+TD)/2)) that is greater than X, whereX=(2,065,292*density of ethylene polymer)−1,872,345, preferably theinventive films have an average modulus of 1.2*X, preferably 1.3*X,preferably 1.4*X.

Preferably, the articles (preferably films) produced herein have anaverage MD/TD modulus of between 30,000 psi and 40,000 psi.

Preferably, the articles (preferably films) produced herein have a dartdrop impact resistance of 600 g/mil or greater.

Preferably, the articles (preferably films) produced herein have a dartdrop impact resistance of 700 g/mil or greater.

Preferably, the films produced herein have an Elmendorf tear resistanceof 300 g/mil or greater in the machine direction (MD).

Preferably, the preferably films produced herein have an Elmendorf tearresistance of 200 g/mil or greater in the machine direction (MD),preferably 300 g/mil or more, preferably 350 g/mil or more.

Preferably, the articles (preferably films) produced herein have a hazeof 12% or less.

Preferably, the ethylene polymers produced herein have an MIR of 35 to55, and a film produced therefrom has an Elmendorf tear resistance of300 g/mil (or at least 450 g/mil or greater or at least 500 g/mil orgreater) in the machine direction (MD), and/or a dart drop impactresistance of at least 500 g/mil or greater (or at least 750 g/mil orgreater, or at least 800 g/mil or greater).

Stretch Films

The polymers and compositions as described above may be utilized toprepare stretch films. Stretch films are widely used in a variety ofbundling and packaging applications. The term “stretch film” indicatesfilms capable of stretching and applying a bundling force, and includesfilms stretched at the time of application as well as “pre-stretched”films, i.e., films which are provided in a pre-stretched form for usewithout additional stretching. Stretch films can be monolayer films ormultilayer films, and can include conventional additives, such ascling-enhancing additives such as tackifiers, and non-cling or slipadditives, to tailor the slip/cling properties of the film.

Shrink Films

The polymers and compositions as described above may be utilized toprepare shrink films. Shrink films, also referred to as heat-shrinkablefilms, are widely used in both industrial and retail bundling andpackaging applications. Such films are capable of shrinking uponapplication of heat to release stress imparted to the film during orsubsequent to extrusion. The shrinkage can occur in one direction or inboth longitudinal and transverse directions. Conventional shrink filmsare described, for example, in WO 2004/022646.

Industrial shrink films are commonly used for bundling articles onpallets. Typical industrial shrink films are formed in a single bubbleblown extrusion process to a thickness of about 80 to 200 μm, andprovide shrinkage in two directions, typically at a machine direction(MD) to transverse direction (TD) ratio of about 60:40.

Retail films are commonly used for packaging and/or bundling articlesfor consumer use, such as, for example, in supermarket goods. Such filmsare typically formed in a single bubble blown extrusion process to athickness of about 35 to 80, μm, with a typical MD:TD shrink ratio ofabout 80:20.

Films may be used in “shrink-on-shrink” applications.“Shrink-on-shrink,” as used herein, refers to the process of applying anouter shrink wrap layer around one or more items that have already beenindividually shrink wrapped (herein, the “inner layer” of wrapping). Inthese processes, it is desired that the films used for wrapping theindividual items have a higher melting (or shrinking) point than thefilm used for the outside layer. When such a configuration is used, itis possible to achieve the desired level of shrinking in the outerlayer, while preventing the inner layer from melting, further shrinking,or otherwise distorting during shrinking of the outer layer. Some filmsdescribed herein have been observed to have a sharp shrinking point whensubjected to heat from a heat gun at a high heat setting, whichindicates that they may be especially suited for use as the inner layerin a variety of shrink-on-shrink applications.

Greenhouse Films

The polymers and compositions as described above may be utilized toprepare stretch to prepare greenhouse films. Greenhouse films aregenerally heat retention films that, depending on climate requirements,retain different amounts of heat. Less demanding heat retention filmsare used in warmer regions or for spring time applications. Moredemanding heat retention films are used in the winter months and incolder regions.

Bags

Bags include those bag structures and bag applications known to thoseskilled in the art. Exemplary bags include shipping sacks, trash bagsand liners, industrial liners, produce bags, and heavy duty bags.

Packaging

Packaging includes those packaging structures and packaging applicationsknown to those skilled in the art. Exemplary packaging includes flexiblepackaging, food packaging, e.g., fresh cut produce packaging, frozenfood packaging, bundling, packaging and unitizing a variety of products.Applications for such packaging include various foodstuffs, rolls ofcarpet, liquid containers, and various like goods normally containerizedand/or palletized for shipping, storage, and/or display.

Blow Molded Articles

The polymers and compositions described above may also be used in blowmolding processes and applications. Such processes are well known in theart, and involve a process of inflating a hot, hollow thermoplasticpreform (or parison) inside a closed mold. In this manner, the shape ofthe parison conforms to that of the mold cavity, enabling the productionof a wide variety of hollow parts and containers.

In a typical blow molding process, a parison is formed between moldhalves and the mold is closed around the parison, sealing one end of theparison and closing the parison around a mandrel at the other end. Airis then blown through the mandrel (or through a needle) to inflate theparison inside the mold. The mold is then cooled and the part formedinside the mold is solidified. Finally, the mold is opened and themolded part is ejected. The process lends itself to any design having ahollow shape, including but not limited to bottles, tanks, toys,household goods, automobile parts, and other hollow containers and/orparts.

Blow molding processes may include extrusion and/or injection blowmolding. Extrusion blow molding is typically suited for the formation ofitems having a comparatively heavy weight, such as greater than about 12ounces, including but not limited to food, laundry, or waste containers.Injection blow molding is typically used to achieve accurate and uniformwall thickness, high quality neck finish, and to process polymers thatcannot be extruded. Typical injection blow molding applications include,but are not limited to, pharmaceutical, cosmetic, and single servingcontainers, typically weighing less than 12 ounces.

Injection Molded Articles

The polymers and compositions described above may also be used ininjection molded applications. Injection molding is a process commonlyknown in the art, and is a process that usually occurs in a cyclicalfashion. Cycle times generally range from 10 to 100 seconds and arecontrolled by the cooling time of the polymer or polymer blend used.

In a typical injection molding cycle, polymer pellets or powder are fedfrom a hopper and melted in a reciprocating screw type injection moldingmachine. The screw in the machine rotates forward, filling a mold withmelt and holding the melt under high pressure. As the melt cools in themold and contracts, the machine adds more melt to the mold tocompensate. Once the mold is filled, it is isolated from the injectionunit and the melt cools and solidifies. The solidified part is ejectedfrom the mold and the mold is then closed to prepare for the nextinjection of melt from the injection unit.

Injection molding processes offer high production rates, goodrepeatability, minimum scrap losses, and little to no need for finishingof parts. Injection molding is suitable for a wide variety ofapplications, including containers, household goods, automobilecomponents, electronic parts, and many other solid articles.

Extrusion Coating

The polymers and compositions described above may be used in extrusioncoating processes and applications. Extrusion coating is a plasticfabrication process in which molten polymer is extruded and applied ontoa non-plastic support or substrate, such as paper or aluminum in orderto obtain a multi-material complex structure. This complex structuretypically combines toughness, sealing and resistance properties of thepolymer formulation with barrier, stiffness or aesthetics attributes ofthe non-polymer substrate. In this process, the substrate is typicallyfed from a roll into a molten polymer as the polymer is extruded from aslot die, which is similar to a cast film process. The resultantstructure is cooled, typically with a chill roll or rolls, and wouldinto finished rolls.

Extrusion coating materials are typically used in food and non-foodpackaging, pharmaceutical packaging, and manufacturing of goods for theconstruction (insulation elements) and photographic industries (paper).

Foamed Articles

The polymers and compositions described above may be used in foamedapplications. In an extrusion foaming process, a blowing agent, such as,for example, carbon dioxide, nitrogen, or a compound that decomposes toform carbon dioxide or nitrogen, is injected into a polymer melt bymeans of a metering unit. The blowing agent is then dissolved in thepolymer in an extruder, and pressure is maintained throughout theextruder. A rapid pressure drop rate upon exiting the extruder creates afoamed polymer having a homogenous cell structure. The resulting foamedproduct is typically light, strong, and suitable for use in a wide rangeof applications in industries such as packaging, automotive, aerospace,transportation, electric and electronics, and manufacturing.

Wire and Cable Applications

Also provided are electrical articles and devices including one or morelayers formed of or comprising the polymers and compositions describedabove. Such devices include, for example, electronic cables, computerand computer-related equipment, marine cables, power cables,telecommunications cables or data transmission cables, and combinedpower/telecommunications cables.

Electrical devices described herein can be formed by methods well knownin the art, such as by one or more extrusion coating steps in areactor/extruder equipped with a cable die. Such cable extrusionapparatus and processes are well known. In a typical extrusion method,an optionally heated conducting core is pulled through a heatedextrusion die, typically a cross-head die, in which a layer of meltedpolymer composition is applied. Multiple layers can be applied byconsecutive extrusion steps in which additional layers are added, or,with the proper type of die, multiple layers can be addedsimultaneously. The cable can be placed in a moisture curingenvironment, or allowed to cure under ambient conditions.

Test Methods

¹H NMR

¹H NMR data was collected at 393K in a 10 mm probe using a Brukerspectrometer with a ¹H frequency of 400 MHz (available from AgilentTechnologies, Santa Clara, Calif.). Data was recorded using a maximumpulse width of 45° C., 5 seconds between pulses and signal averaging 512transients. Spectral signals were integrated and the number ofunsaturation types per 1000 carbons was calculated by multiplying thedifferent groups by 1000 and dividing the result by the total number ofcarbons. M_(n) was calculated by dividing the total number ofunsaturated species into 14,000, and has units of g/mol.

TREF Method

Unless otherwise indicated, the TREF-LS data reported herein weremeasured using an analytical size TREF instrument (Polymerchar, Spain),with a column of the following dimension: inner diameter (ID) 7.8 mm andouter diameter (OD) 9.53 mm and a column length of 150 mm. The columnwas filled with steel beads. 0.5 mL of a 6.4% (w/v) polymer solution inorthodichlorobenzene (ODCB) containing 6 g BHT/4 L were charged onto thecolumn and cooled from 140° C. to 25° C. at a constant cooling rate of1.0° C./min. Subsequently, the ODCB was pumped through the column at aflow rate of 1.0 ml/min and the column temperature was increased at aconstant heating rate of 2° C./min to elute the polymer. The polymerconcentration in the eluted liquid was detected by means of measuringthe absorption at a wavenumber of 2857 cm⁻¹ using an infrared detector.The concentration of the ethylene-α-olefin copolymer in the elutedliquid was calculated from the absorption and plotted as a function oftemperature. The molecular weight of the ethylene-α-olefin copolymer inthe eluted liquid was measured by light scattering using a MinidawnTristar light scattering detector (Wyatt, Calif., USA). The molecularweight was also plotted as a function of temperature.

GPC 4D Procedure: Molecular Weight, Comonomer Composition and Long ChainBranching Determination by GPC-IR Hyphenated with Multiple Detectors

The distribution and the moments of molecular weight (M_(w), M_(n),M_(w)/M_(n), etc.), the comonomer content (C₂, C₃, C₆, etc.) and thebranching index (g′vis) are determined by using a high temperature GelPermeation Chromatography (Polymer Char GPC-IR) equipped with amultiple-channel band-filter based Infrared detector IR5, an 18-anglelight scattering detector and a viscometer. Three Agilent PLgel 10-μmMixed-B LS columns are used to provide polymer separation. Aldrichreagent grade 1,2,4-trichlorobenzene (TCB) with 300 ppm antioxidantbutylated hydroxytoluene (BHT) is used as the mobile phase. The TCBmixture is filtered through a 0.1 μm Teflon filter and degassed with anonline degasser before entering the GPC instrument. The nominal flowrate is 1.0 ml/min and the nominal injection volume is 200 μL. The wholesystem including transfer lines, columns, and detectors are contained inan oven maintained at 145° C. The polymer sample is weighed and sealedin a standard vial with 80 μL flow marker (Heptane) added to it. Afterloading the vial in the autosampler, polymer is automatically dissolvedin the instrument with 8 ml added TCB solvent. The polymer is dissolvedat 160° C. with continuous shaking for about 1 hour for PE samples or 2hour for PP samples. The TCB densities used in concentration calculationare 1.463 g/ml at about 23° C. temperature and 1.284 g/ml at 145° C. Thesample solution concentration is from 0.2 to 2.0 mg/ml, with lowerconcentrations being used for higher molecular weight samples. Theconcentration (c), at each point in the chromatogram is calculated fromthe baseline-subtracted IR5 broadband signal intensity (I), using thefollowing equation: c=/βI, where β is the mass constant. The massrecovery is calculated from the ratio of the integrated area of theconcentration chromatography over elution volume and the injection masswhich is equal to the pre-determined concentration multiplied byinjection loop volume. The conventional molecular weight (IR MW) isdetermined by combining universal calibration relationship with thecolumn calibration which is performed with a series of monodispersedpolystyrene (PS) standards ranging from 700 to 10M gm/mole. The MW ateach elution volume is calculated with following equation:

${{\log\; M} = {\frac{\log\left( {K_{PS}/K} \right)}{a + 1} + {\frac{a_{PS} + 1}{a + 1}\log\; M_{PS}}}},$where the variables with subscript “PS” stand for polystyrene whilethose without a subscript are for the test samples. In this method,α_(PS)=0.67 and K_(PS)=0.000175 while α and K are for other materials ascalculated and published in literature (Sun, T. et al. Macromolecules2001, 34, 6812), except that for purposes of this invention and claimsthereto, α=0.695 and K=0.000579 for linear ethylene polymers, α=0.705and K=0.0002288 for linear propylene polymers, α=0.695 and K=0.000181for linear butene polymers, α is 0.695 and K is0.000579*(1−0.0087*w2b+0.000018*(w2b){circumflex over ( )}2) forethylene-butene copolymer where w2b is a bulk weight percent of butenecomonomer, α is 0.695 and K is 0.000579*(1−0.0075*w2b) forethylene-hexene copolymer where w2b is a bulk weight percent of hexenecomonomer, and α is 0.695 and K is 0.000579*(1−0.0077*w2b) forethylene-octene copolymer where w2b is a bulk weight percent of octenecomonomer. Concentrations are expressed in g/cm³, molecular weight isexpressed in g/mole, and intrinsic viscosity (hence K in theMark-Houwink equation) is expressed in dL/g unless otherwise noted.

The comonomer composition is determined by the ratio of the IR5 detectorintensity corresponding to CH₂ and CH₃ channel calibrated with a seriesof PE and PP homo/copolymer standards whose nominal value arepredetermined by NMR or FTIR. In particular, this provides the methylsper 1000 total carbons (CH₃/1000TC) as a function of molecular weight.The short-chain branch (SCB) content per 1000TC (SCB/1000TC) is thencomputed as a function of molecular weight by applying a chain-endcorrection to the CH₃/1000TC function, assuming each chain to be linearand terminated by a methyl group at each end. The wt % comonomer is thenobtained from the following expression in which ƒ is 0.3, 0.4, 0.6, 0.8,and so on for C3, C4, C6, C8, and so on co-monomers, respectively:w2=ƒ*SCB/1000TC.

The bulk composition of the polymer from the GPC-IR and GPC-4D analysesis obtained by considering the entire signals of the CH₃ and CH₂channels between the integration limits of the concentrationchromatogram. First, the following ratio is obtained

${{Bulk}\mspace{14mu}{IR}\mspace{14mu}{ratio}} = {\frac{{Area}\mspace{14mu}{of}\mspace{14mu}{CH}_{3}\mspace{14mu}{signal}\mspace{14mu}{within}\mspace{14mu}{integration}\mspace{14mu}{limits}}{{Area}\mspace{14mu}{of}\mspace{14mu}{CH}_{2}\mspace{14mu}{signal}\mspace{14mu}{within}\mspace{14mu}{integration}\mspace{14mu}{limits}}.}$

Then the same calibration of the CH₃ and CH₂ signal ratio, as mentionedpreviously in obtaining the CH3/1000TC as a function of molecularweight, is applied to obtain the bulk CH3/1000TC. A bulk methyl chainends per 1000TC (bulk CH3end/1000TC) is obtained by weight-averaging thechain-end correction over the molecular-weight range. Thenw2b=ƒ*bulk CH3/1000TCbulk SCB/1000TC=bulk CH3/1000TC−bulk CH3end/1000TCand bulk SCB/1000TC is converted to bulk w2 in the same manner asdescribed above.

The LS detector is the 18-angle Wyatt Technology High Temperature DAWNHELEOSII. The LS molecular weight (M) at each point in the chromatogramis determined by analyzing the LS output using the Zimm model for staticlight scattering (Light Scattering from Polymer Solutions; Huglin, M.B., Ed.; Academic Press, 1972.):

$\frac{K_{o}c}{\Delta\;{R(\theta)}} = {\frac{1}{M\;{P(\theta)}} + {2A_{2}{c.}}}$

Here, ΔR(θ) is the measured excess Rayleigh scattering intensity atscattering angle θ, c is the polymer concentration determined from theIR5 analysis, A2 is the second virial coefficient, P(θ) is the formfactor for a monodisperse random coil, and Ko is the optical constantfor the system:

${K_{o} = \frac{4\pi^{2}{n^{2}\left( {d\;{n/{dc}}} \right)}^{2}}{\lambda^{4}N_{A}}},$where NA is Avogadro's number, and (dn/dc) is the refractive indexincrement for the system. The refractive index, n=1.500 for TCB at 145°C. and λ=665 nm. For analyzing polyethylene homopolymers,ethylene-hexene copolymers, and ethylene-octene copolymers, dn/dc=0.1048ml/mg and A2=0.0015; for analyzing ethylene-butene copolymers,dn/dc=0.1048*(1−0.00126*w2) ml/mg and A2=0.0015 where w2 is weightpercent butene comonomer.A high temperature Agilent (or Viscotek Corporation) viscometer, whichhas four capillaries arranged in a Wheatstone bridge configuration withtwo pressure transducers, is used to determine specific viscosity. Onetransducer measures the total pressure drop across the detector, and theother, positioned between the two sides of the bridge, measures adifferential pressure. The specific viscosity, ηs, for the solutionflowing through the viscometer is calculated from their outputs. Theintrinsic viscosity, [η], at each point in the chromatogram iscalculated from the equation [η]=ηs/c, where c is concentration and isdetermined from the IR5 broadband channel output. The viscosity MW ateach point is calculated asM=K _(PS) M ^(α) ^(PS) ⁺¹/[η], where α_(ps) is 0.67 and K _(ps) is0.000175.

The branching index (g′vis) is calculated using the output of theGPC-IR5-LS-VIS method as follows. The average intrinsic viscosity,[η]avg, of the sample is calculated by:

${\lbrack\eta\rbrack_{avg} = \frac{\sum{c_{i}\lbrack\eta\rbrack}_{i}}{\sum c_{i}}},$where the summations are over the chromatographic slices, i, between theintegration limits. The branching index g′vis is defined as

${g_{vis}^{\prime} = \frac{\lbrack\eta\rbrack_{avg}}{K\; M_{v}^{\alpha}}},$where Mv is the viscosity-average molecular weight based on molecularweights determined by LS analysis and the K and α are for the referencelinear polymer, which are, for purposes of this invention and claimsthereto, α=0.695 and K=0.000579 for linear ethylene polymers, α=0.705and K=0.0002288 for linear propylene polymers, α=0.695 and K=0.000181for linear butene polymers, α is 0.695 and K is0.000579*(1−0.0087*w2b+0.000018*(w2b){circumflex over ( )}2) forethylene-butene copolymer where w2b is a bulk weight percent of butenecomonomer, α is 0.695 and K is 0.000579*(1−0.0075*w2b) forethylene-hexene copolymer where w2b is a bulk weight percent of hexenecomonomer, and α is 0.695 and K is 0.000579*(1−0.0077*w2b) forethylene-octene copolymer where w2b is a bulk weight percent of octenecomonomer. Concentrations are expressed in g/cm³, molecular weight isexpressed in g/mole, and intrinsic viscosity (hence K in theMark-Houwink equation) is expressed in dL/g unless otherwise noted.Calculation of the w2b values is as discussed above.

The reversed-co-monomer index (RCI,m) is computed from x2 (mol %co-monomer C₃, C₄, C₆, C₈, etc.), as a function of molecular weight,where x2 is obtained from the following expression in which n is thenumber of carbon atoms in the comonomer (3 for C₃, 4 for C₄, 6 for C₆,etc.):

${x\; 2} = {- {\frac{200w\; 2}{{{- 100}n} - {2w\; 2} + {n\; w\; 2}}.}}$Then the molecular-weight distribution, W(z) where z=log₁₀ M, ismodified to W′(z) by setting to 0 the points in W that are less than 5%of the maximum of W; this is to effectively remove points for which theS/N in the composition signal is low. Also, points of W′ for molecularweights below 2000 gm/mole are set to 0. Then W′ is renormalized so that1=∫_(−∞) ^(∞) W′dz,and a modified weight-average molecular weight (M_(w)′) is calculatedover the effectively reduced range of molecular weights as follows:M _(w)′=∫_(−∞) ^(∞)10^(z) *W′dz.

The RCI,m is then computed asRCI,m=∫ _(−∞) ^(∞) x2(10^(z) −M _(w)′)W′dz.

A reversed-co-monomer index (RCI,w) is also defined on the basis of theweight fraction co-monomer signal (w2/100) and is computed as follows:

${RCI},{w = {\int_{- \infty}^{\infty}{\frac{w\; 2}{100}\left( {10^{z} - M_{w}^{\prime}} \right)W^{\prime}d\;{z.}}}}$

In the above definite integrals the limits of integration are the widestpossible for the sake of generality; however, in reality the function isonly integrated over a finite range for which data is acquired,considering the function in the rest of the non-acquired range to be 0.Also, by the manner in which W′ is obtained, it is possible that W′ is adiscontinuous function, and the above integrations need to be donepiecewise.

Three co-monomer distribution ratios are also defined on the basis ofthe % weight (w2) comonomer signal, denoted as CDR-1,w, CDR-2,w, andCDR-3,w, as follows:

${{CDR}\text{-}1},{w = \frac{w\; 2\left( {M\; z} \right)}{w\; 2\left( {M\; w} \right)}},{{CDR}\text{-}2},{w = \frac{w\; 2\left( {M\; z} \right)}{w\; 2\left( \frac{{M\; w} + {M\; n}}{2} \right)}},{{CDR}\text{-}3},{w = \frac{w\; 2\left( \frac{{M\; z} + {M\; w}}{2} \right)}{w\; 2\left( \frac{{M\; w} + {M\; n}}{2} \right)}},$where w2(Mw) is the % weight co-monomer signal corresponding to amolecular weight of Mw, w2(Mz) is the % weight co-monomer signalcorresponding to a molecular weight of Mz, w2[(Mw+Mn)/2)] is the %weight co-monomer signal corresponding to a molecular weight of(Mw+Mn)/2, and w2[(Mz+Mw)/2] is the % weight co-monomer signalcorresponding to a molecular weight of Mz+Mw/2, where Mw is theweight-average molecular weight, Mn is the number-average molecularweight, and Mz is the z-average molecular weight.

Accordingly, the co-monomer distribution ratios can be also definedutilizing the % mole co-monomer signal, CDR-1,m, CDR-2,m, CDR-3,m, as

${{CDR}\text{-}1},{m = \frac{x\; 2\left( {M\; z} \right)}{x\; 2\left( {M\; w} \right)}},{{CDR}\text{-}2},{m = \frac{x\; 2\left( {M\; z} \right)}{x\; 2\left( \frac{{M\; w} + {M\; n}}{2} \right)}},{{CDR}\text{-}3},{m = \frac{x\; 2\left( \frac{{M\; z} + {M\; w}}{2} \right)}{x\; 2\left( \frac{{M\; w} + {M\; n}}{2} \right)}},$where x2(Mw) is the % mole co-monomer signal corresponding to amolecular weight of Mw, x2(Mz) is the % mole co-monomer signalcorresponding to a molecular weight of Mz, x2[(Mw+Mn)/2)] is the % moleco-monomer signal corresponding to a molecular weight of (Mw+Mn)/2, andx2[(Mz+Mw)/2] is the % mole co-monomer signal corresponding to amolecular weight of Mz+Mw/2, where Mw is the weight-average molecularweight, Mn is the number-average molecular weight, and Mz is thez-average molecular weight.Cross-Fractionation Chromatography (CFC)

Cross-fractionation chromatography (CFC) analysis was done using a CFC-2instrument from Polymer Char, S.A., Valencia, Spain. The principles ofCFC analysis and a general description of the particular apparatus usedare given in the article by Ortin, A.; Monrabal, B.; Sancho-Tello, 257J. MACROMOL. SYMP. 13 (2007). A general schematic of the apparatus usedis shown in FIG. 1 of this article. Pertinent details of the analysismethod and features of the apparatus used are as follows.

The solvent used for preparing the sample solution and for elution was1,2-dichlorobenzene (ODCB) which was stabilized by dissolving 2 g of2,6-bis(1,1-dimethylethyl)-4-methylphenol (butylated hydroxytoluene) ina 4-L bottle of fresh solvent at ambient temperature. The sample to beanalyzed (25-125 mg) was dissolved in the solvent (25 ml metered atambient temperature) by stirring (200 rpm) at 150° C. for 75 min. Asmall volume (0.5 ml) of the solution was introduced into a TREF column(stainless steel; o.d., ⅜″; length, 15 cm; packing, non-porous stainlesssteel micro-balls) at 150° C., and the column temperature was stabilizedfor 30 min at a temperature (120-125° C.) approximately 20° C. higherthan the highest-temperature fraction for which the GPC analysis wasincluded in obtaining the final bivariate distribution. The samplevolume was then allowed to crystallize in the column by reducing thetemperature to an appropriate low temperature (30, 0, or −15° C.) at acooling rate of 0.2° C./min. The low temperature was held for 10 minbefore injecting the solvent flow (1 ml/min) into the TREF column toelute the soluble fraction (SF) into the GPC columns (3×PLgel 10 μmMixed-B 300×7.5 mm, Agilent Technologies, Inc.); the GPC oven was heldat high temperature (140° C.). The SF was eluted for 5 min from the TREFcolumn and then the injection valve was put in the “load” position for40 min to completely elute all of the SF through the GPC columns(standard GPC injections). All subsequent higher-temperature fractionswere analyzed using overlapped GPC injections wherein at eachtemperature step the polymer was allowed to dissolve for at least 16 minand then eluted from the TREF column into the GPC column for 3 min. TheIR4 (Polymer Char) infrared detector was used to generate an absorbancesignal that is proportional to the concentration of polymer in theeluting flow.

The universal calibration method was used for determining the molecularweight distribution (MwD) and molecular-weight averages (M_(n), M_(w),etc.) of eluting polymer fractions. Thirteen narrow molecular-weightdistribution polystyrene standards (obtained from Agilent Technologies,Inc.) within the range of 1.5-8200 kg/mol were used to generate auniversal calibration curve. Mark-Houwink parameters were obtained fromAppendix I of Mori, S.; Barth, H. G. Size Exclusion Chromatography;Springer, 1999. For polystyrene K=1.38×10⁻⁴ dl/g and α=0.7; and forpolyethylene K=5.05×10⁻⁴ dl/g and α=0.693 were used. For a polymerfraction, which eluted at a temperature step, that has a weight fraction(weight % recovery) of less than 0.5%, the MwD and the molecular-weightaverages were not computed; additionally, such polymer fractions werenot included in computing the MwD and the molecular-weight averages ofaggregates of fractions.

Measuring Tw1, Tw2, Mw1 and Mw2 from CFC

A new technique has been developed for determining both MwD and SCBDcompositional information, using cryogenic cross fractionation (cryoCFC), to compare the experimental polymers to competitive products onthe market. The procedures for the determination of CFC data arediscussed in more detail below.

In the section of “Fraction summary” in the CFC data file, each fractionis listed by its fractionation temperature (Ti) along with itsnormalized wt. % value (Wi), cumulative wt. %, i.e., Sum wt. on FIG. 3and FIG. 4, and various moments of molecular weight averages (includingweight average molecular weight, Mwi).

FIG. 3 and FIG. 4 are plots that graphically illustrate the calculationsused to determine the CFC result. Only fractions having MwD data areconsidered. In both FIG. 3 and FIG. 4, the x-axis represents the elutiontemperature in centigrade, while the right hand y-axis represents thevalue of the integral of the weights of polymer that have been eluted upto an elution temperature. The temperature at which 100% of the materialhas eluted in this example is about 100° C. The closest point at which50% of the polymer has eluted is determined by the integral, which isused then to divide each of the plots into a 1^(st)-half and a2^(nd)-half.

To calculate values of Tw1, Tw2, Mw1 and Mw2, the data in “Fractionsummary” was divided into two roughly equal halves. Weight averages ofTi and Mwi; for each half were calculated according to the conventionaldefinition of weight average. Fractions which did not have sufficientquantity (i.e., <0.5 wt. %) to be processed for molecular weightaverages in the original data file were excluded from the calculation ofTw1, Tw2, Mw1 and Mw2.

The first part of the process is illustrated by FIG. 3. From the sectionof fraction summary in the CFC data file, the fraction whose cumulativewt. % (i.e., Sum wt) is closest to 50 is identified (e.g., the fractionat 84° C. on FIG. 3). The Fraction summary data is divided into twohalves, e.g., Ti<=84° C. as the 1st half and Ti>84° C. as the 2nd halfon FIG. 3. Fractions which do not have molecular weight averagesreported in the original data file are excluded, e.g., excluding thefractions with Ti between 25° C. and 40° C. on FIG. 3.

In FIG. 3, the left hand y-axis represents the wt % of the elutedfraction. Using the procedure above to divide the curves into twohalves, these values are used to calculate the weight average elutiontemperature for each half using the formula shown in Eqn. 1.

$\begin{matrix}{{{T\; w} = \frac{\sum{T\; i\; W\; i}}{\sum{W\; i}}},} & {{Eqn}.\mspace{14mu} 1}\end{matrix}$

In Eqn. 1, Ti represents the elution temperature for each elutedfraction, and Wi represents the normalized weight % (polymer amount) ofeach eluted fraction. For the example shown in FIG. 3, this provides aweight average elution temperature of 64.9° C. for the first half, and91.7° C. for the second half.

In FIG. 4, the left hand axis represents the weight average molecularweight (Mwj) of each eluted fraction. These values are used to calculatethe weight average molecular weight for each half using the formulashown in Eqn. 2.

$\begin{matrix}{{{M\; w} = \frac{\sum{M\; w\; i\; W\; i}}{\sum{W\; i}}},} & {{Eqn}.\mspace{14mu} 2}\end{matrix}$

In Eqn. 2, Mw; represents the weight average molecular weight of eacheluted fraction, and Wj represents the normalized weight % (polymeramount) of each eluted fraction. For the example shown in FIG. 4, thisprovides a weight average molecular weight of 237,539 g/mole for thefirst half, and 74,156 g/mole for the second half. The values calculatedusing the techniques described above may be used to classify theMWD×SCBD for experimental polymers and control polymers.

FIG. 5 is a semi-log plot of (Mw1/Mw2) vs. (Tw1−Tw2) designed to showthe important differences in MWD/SCBD combination among inventiveexamples vs. commercial benchmarks. Such differences are believed toplay a key role in determining the trade-off pattern and/or balance ofvarious performance attributes such as stiffness, toughness andprocessability.

Additional test methods include the following.

Test Name Method or description Melt Index (I₂), ASTM D-1238 2.16 kg(MI) or 21.6 kg (HLMI), 190° C. High Load Melt Index (I₂₁) Density ASTMD1505, column density. Samples were molded under ASTM D4703- 10a,Procedure C , then conditioned under ASTM D618-08 (23° ± 2° C. and 50 ±10% Relative Humidity) for 40 hours before testing 1% Secant ASTM D-882,15 mm width strip Modulus Yield Strength ASTM D-882, 15 mm width stripTensile Strength ASTM D-882, 15 mm width strip Elongation at ASTM D-882,15 mm width strip Break Elongation at ASTM D-882, 15 mm width stripYield Dart Drop ASTM D-1709, Phenolic, Method A Haze ASTM D-1003 Gloss,45° ASTM D-2457 Elmendorf Tear ASTM D1922 with ASTM Conditioning for 40Hours at 23° ± 2° C. and 50 ± 10% Relative Humidity Puncture ModifiedASTM D5748: ASTM probe was used with two 0.25 mil HDPE slip sheets.Machine Model: United SFM-1. Testing speed: 10 in/min Heat Seal Methodusing 1 inch film strip of 1 mil gauge, sealed at various temperaturesunder 73 psi (0.5 N/mm²) for 1 second. Following ASTM Conditioning for40 Hours at 23° ± 2° C. and 50 ± 10% Relative Humidity, the sealedspecimen were tested in T-joint peel mode at 20 inch/min pulling speedHot tack Method using 1 inch film strip of 1 mil gauge, sealed atvarious temperatures under 73 psi (0.5 N/mm²) for 0.5 second. After a0.4 second delay, the sealed specimen were pulled at 200 mm/speed inT-joint peel mode MD = machine direction TD = transverse direction

Unless otherwise indicated, room/ambient temperature is approximately23° C.

EXAMPLES

It is to be understood that while the invention has been described inconjunction with the specific embodiments thereof, the foregoingdescription is intended to illustrate and not limit the scope of theinvention. Other aspects, advantages and modifications will be apparentto those skilled in the art to which the invention pertains.

Therefore, the following examples are put forth so as to provide thoseskilled in the art with a complete disclosure and description and arenot intended to limit the scope of that which the inventors regard astheir invention.

ES70-875 silica is ES70™ silica (PQ Corporation, Conshohocken, Pa.) thathas been calcined at approx. 875° C. and stored under nitrogen.Specifically, the ES70™ silica is calcined at 880° C. for four hoursafter being ramped to 880° C. according to the following ramp rates:

° C. ° C./h ° C. ambient 100 200 200 50 300 300 133 400 400 200 800 80050 880

Catalyst systems (i.e., mixed/dual catalyst systems) were prepared usinghafnocene (bis(n-propylCp)HfMe₂) and zirconocenes (rac/meso bis(1-Me-Ind)ZrMe₂) and (rac/meso bis (1-Ee-Ind)ZrMe₂), where Me=methyl,Eth=ethyl, Ind=indenyl. Dimethyl leaving groups for the metalloceneswere employed although di-chloro versions of the catalyst could havealso been employed.

Upon evaluation and testing to produce LLDPE products, the resultsrevealed high catalyst activity and unique BOCD LLDPE products.

Herein, we have found that by varying the ratio of the catalyst ofFormula A (e.g., (nPrCp)₂HfMe₂) to the catalyst of Formula B (e.g.,rac/meso(1-EthInd)₂ZrMe₂) in the support, the polymer composition wastuned to a BOCD composition that yielded a surprisingly good combinationof film mechanical properties and resin processability. Specifically, asupported mixed catalyst on ES70-875 silica was prepared with(nPrCp)₂HfMe₂ to rac/meso(1-EthInd)₂ZrMe₂ at ratios varying from 85:15to 70:30. Linear low density polyethylene resins were obtained from apilot plant gas phase reactor using this mixed catalyst system. A 0.65MI, 0.9200 density PE resin was produced that yielded both excellentprocessability (MIR 41) and very good mechanical properties, dart drop(Phenolic Method A) g/ml 735, MD Tear 369 g/ml, 1% Secant (psi) 41,045for a 1 mil film. The corresponding 0.7 mil film yielded dart drop(Phenolic Method A) g/ml 835, MD Tear 637 g/ml, 1% Secant (psi) 36,994

All manipulations were performed in an inert N₂ purged glove box unlessotherwise stated. All anhydrous solvents were purchased from FisherChemical and were degassed and dried over molecular sieves prior to use.Hafnium tetrachloride (HfCl₄) 99+%, and zirconium tetrachloride (ZrCl₄)99+% were purchased from Strem Chemicals and used as received.Methylalumoxane (30 wt % in toluene) was used as received fromAlbemarle. (nPrCp)₂HfCl₂ was obtained from Boulder Scientific. The ¹HNMR measurements were recorded on a 400 MHz Bruker spectrometer.

Synthesis of Rac-meso-bis(1-Ethyl-indenyl)zirconium dimethyl,(1-EtInd)₂ZrMe₂

In a 500 mL round bottom flask, a solid ZrCl₄ (9.42 g, 40.4 mmol) wasslurried with 250 mL of dimethoxyethane (DME) and cooled to −25° C. Asolid lithium-1-ethyl-indenyl (12.13 g, 80.8 mmol) was added over aperiod of 5-10 minutes, and then the reaction mixture was graduallywarmed to room temperature. The resulting orange-yellow mixture washeated at 80° C. for 1 hour to ensure the formation ofbis(1-ethyl-indenyl)zirconium dichloride. The mixture was clear at firstand then byproduct (LiCl) was precipitated out over a course ofreaction, revealing the product formation. Without further purification,the reaction mixture of bis(1-ethyl-indenyl)zirconium dichloride wascooled to −25° C., and to this an ethereal solution of methylmagnesiumbromide (27.0 mL, 80.8 mmol, 3.0 M solution in diethyl ether) was addedover a period of 10-15 minutes. The resulting mixture was slowly turnedto pale yellow and then maroon over a course of reaction andcontinuously stirred overnight at room temperature. Volatiles wereremoved in vacuo. The crude materials were then extracted with hexane(50 mL×5), and subsequent solvent removal afforded to the formation of(1-EtInd)₂ZrMe₂ as an off-white solid in 13.0 g (78.9%) yield. The ¹HNMR spectrum of final material integrated a 1:1 ratio of rac/mesoisomers. ¹H NMR (400 MHz, C₆D₆): δ −1.38 (3H, s, Zr—CH₃, meso), −0.88(6H, s, Zr—CH₃, rac), −0.30 (3H, s, Zr—CH₃, meso), 1.10-1.04 (12H, m,Et-CH₃), 2.41-2.52 (4H, m, Et-CH₂), 2.67-2.79 (4H, m, Et-CH₂), 5.46-5.52(8H, m, Ind-CH), 6.90-6.96 (8H, m, Ar—CH), 7.08-7.15 (4H, m, Ar—CH),7.28-7.22 (4H, m, Ar—CH) ppm.

Preparation of Supported Catalyst

Mixed Catalyst Prep 1: HfP:EtIndZrMe2, 75:25/ES70-875: A 734 gram amountof ES70-875 was added to a solution of 925 grams of 30 wt % MAO dilutedwith 1600 grams of toluene over a 20 minute period and stirred at 120RPM. The temperature was raised to 100° C. and stirred for 180 minutes.The reactor was then cooled during a 120 minute time period, after which3.14 grams of rac/meso(1-EthInd)₂ZrMe₂ and 9.77 grams of (nPrCp)₂HfMe₂were added to the slurry and stirred for 75 minutes. The RPM stir ratewas reduced to 8 RPM and the slurry was dried in a vacuum for 60 hoursyielding a yellow free flowing powder.

Mixed Catalyst Prep 2: HfP:EtIndZrMe2, 70:30/ES70-875: A 734 gram amountof ES70-875 was added to a solution of 925 grams of 30 wt % MAO dilutedwith 1600 grams of toluene over a 20 minute period and stirred at 120RPM. The temperature was raised to 100° C. and stirred for 180 minutes.The reactor was then cooled during a 120 minute time period, after which3.67 grams of rac/meso(1-EthInd)₂ZrMe₂ and 8.65 grams of (nPrCp)₂HfMe₂were added to the slurry and stirred for 75 minutes. The RPM stir ratewas reduced to 8 RPM and the slurry was dried in a vacuum for 60 hoursyielding a yellow free flowing powder.

Polymerization

Polymerization was performed in an 18.5 foot tall gas-phase fluidizedbed reactor with a 22.5″ diameter straight section. Cycle and feed gaseswere fed into the reactor body through a perforated distributor plate,and the reactor was controlled at 290-300 psig and 60-75 mol % ethylene.Reactor temperature was maintained by heating the cycle gas. The use ofdifferent poor comonomer incorporators can be used to alter theproperties of the resulting polymer. Using mixed catalyst 1 yieldedresin with a lower melt index ratio than mixed catalyst system 2. Thepolymerization conditions and properties of the polymer produced in eachexperimental run is set forth in Table 1.

TABLE 1 Run Example-1a Example-2a Example-3a Example-4a Example-5aExample-6a Comparative-4a MI g/10 min 0.97 0.94 0.93 0.65 0.66 0.51 0.46GHLMI g/10 min 33.88 34.87 49.71 27.01 35.33 22.29 12.39 MIR (GHLMI/MI)34.83 37.04 53.51 41.43 53.02 43.71 27.19 Density g/cc 0.9199 0.92040.9195 0.9200 0.9199 0.9169 0.9155 Bed F. 185.0 185.0 175.0 185.0 175.0182.0 173.4 temperature Reactor psig 300.0 300.0 300.0 300.0 300.0 300.0289.8 pressure Ethylene mol % 70.00 69.97 70.02 69.99 70.00 69.97 64.04concentration Ethylene psia 220.3 220.2 220.4 220.3 220.2 220.2 195.0partial pressure H2/C2 = gas ppm/mol % 5.50 5.55 5.53 4.58 4.77 4.274.23 ratio H2 ppm 385 388 387 321 334 299 271 concentration C6/C2 = gasmolar 0.019 0.020 0.021 0.021 0.022 0.025 0.015 ratio C6/C2 = flow lb/lb0.096 0.103 0.110 0.102 0.108 0.125 0.098 ratio iC5 mol % 5.1 4.9 4.85.3 5.0 4.9 5.8 concentration Bed weight lb 730 750 735 751 727 746 754Fluidized lb/ft3 19.17 20.08 19.51 20.15 19.54 20.04 19.28 bulk densitySettled bulk lb/ft3 28.50 29.55 29.03 29.39 28.87 29.11 28.25 densityProduction lb/h 140 141 141 133 136 134 127 rate Catalyst feed g/h 9.878.06 8.06 8.06 8.06 8.06 9.77 rate Catalyst lb/lb 7206 7695 7825 75157818 7540 5929 productivity Residence h 5.22 5.31 5.22 5.63 5.35 5.575.94 time

Cross-fractionation chromatography (CFC) analysis was done in accordancewith the test methods described herein and the data and results areprovided in Tables 2, 3, and 4.

TABLE 2 Mw Activity Mixed MI (LS) Mn Mz Hexene gP/gsup. g′ ExampleCatalysts dg/min MIR g/mol g/mol g/mol Mz/Mn Mw/Mn Mz/Mw wt % Cat. (vis)1a 1 0.97 35 119877 11514 332279 28.8 10.4 2.77 8.34 7206 0.962 2a 20.94 35 122808 11678 366270 31.4 10.5 2.98 8.48 7695 0.964 3a 2 0.93 54128411 11575 417994 36.1 11.1 3.25 9.50 7825 0.945 4a 2 0.65 41 13701910236 451098 44.1 13.4 3.29 8.60 7515 0.963 5a 2 0.66 53 139487 11898463860 40.0 11.7 3.32 9.03 7695 0.940 6a 2 0.51 44 158217 13541 47166034.8 11.7 2.98 10.26 7540 0.957 Comparative- Comp. 0.46 27 150953 28903348081 12.0 5.22 2.30 9.29 4703 0.986 4a

TABLE 3 RCI, Mixed MI m (LS) CDR2, T₇₅-T₂₅ Part Catalysts dg/min MIR(kg/mol) m (° C.) 1a 1 0.97 35 168 1.77 2a 2 0.94 35 205 1.88 3a 2 0.9354 311 2.38 4a 2 0.65 41 250 2.04 5a 2 0.66 53 337 2.38 6a 2 0.51 44 3582.08 Comparative-4a Comp. 0.46 27 193 1.83

TABLE 4 Catalyst CFC Mw1/ Tw1- (log(Mw1/Mw2))/ system File # DescriptionMw1 Mw2 Tw1 Tw2 Mw2 Tw2 (Tw1-Tw2) 1 1a 249,694 79,700 64.6 87.1 3.13−22.6 −0.0220 2 5a 306,177 69,012 58.2 88.3 4.44 −30.1 −0.0215 2 3a288,700 62,997 58.0 88.0 4.58 −30.0 −0.0220 2 2a 240,901 67,339 62.087.7 3.58 −25.7 −0.0215 2 4a 303,123 78,855 62.0 88.2 3.84 −26.3 −0.02232 6a 336,080 77,228 55.5 86.7 4.35 −31.3 −0.0204 Evolue 3010 148,115166,038 60.3 88.4 0.89 −28.1 0.0018 (926/0.8 n.a.) Elite 5400 174,160109,611 62.0 85.8 1.59 −23.8 −0.0085 (918/1.1/32) Dowlex 2045 117,305238,061 66.4 88.0 0.49 −21.6 0.0142 (920/1.0/29) Borstar FB 2230 268,435371,505 53.5 91.4 0.72 −37.9 0.0037 (923/0.2/110)Film Properties

Blown film evaluations of the inventive polymers from Table 1 werecarried out on a monolayer Alpine-II film line at 60 mil die gap and 2.5BUR using a 65 mm grooved-feed extruder. Further process data is foundin Tables 6 and 8 below. Film properties at 0.7 mil gauge are summarizedin Table 5 and properties at 1.0 mil gauge are summarized in Table 7.

TDA is the total defect area. It is a measure of defects in a filmspecimen, and reported as the accumulated area of defects in squaremillimeters (mm²) normalized by the area of film in square meters (m²)examined, thus having a unit of (mm²/m²) or “ppm”. In the table below,only defects with a dimension above 200 microns are reported.

TDA is obtained by an Optical Control System (OCS). This system consistsof a small extruder (ME20 2800), cast film die, chill roll unit (ModelCR-9), a winding system with good film tension control, and an on-linecamera system (Model FSA-100) to examine the cast film generated foroptical defects. The testing conditions for the cast film generationwere:

1) Extruder temperature setting (° C.): Feed throat/Zone 1/Zone 2/Zone3/Zone 4/Die: 70/190/200/210/215/215; 2) Extruder speed: 50 rpm; 3)Chill roll temperature: 30° C.; and 4) Chill roll speed: 3.5 m/min.

The system generates a cast film of about 4.9 inch in width and anominal gauge of 2 mil. Melt temperature varies with materials, and istypically around 215° C.

Films of 0.7 mil thickness were made for each of the polymers of Table 1under the conditions set forth in Table 6. The properties of such filmsare reported in Table 5.

TABLE 5 Example- Example- Example- Example- Example- Example-Comparative- Comparative- 1a 2a 3a 4a 5a 6a 1a 4a 12 (g/10 min) 1.0 1.01.0 0.7 0.7 0.5 1 0.5 MIR 35 40 54 44 53 49 16 26 Density 0.922 0.9220.922 0.922 0.922 0.917 0.919 0.917 (g/cm3) Gauge Mic (mils) Average0.70 0.67 0.69 0.69 0.69 0.70 0.66 0.68 1% Secant (psi) MD 32,434 34,74132,464 31,567 27,081 24,841 20,425 24,634 TD 38,118 41,696 43,604 42,42140,006 39,005 25,780 32,204 Tensile Yield Strength (psi) MD 1,567 1,5861,527 1,555 1,555 1,455 1,353 1,322 TD 1,602 1,685 1,643 1,705 1,7181,612 1,334 1,426 Tensile Strength (psi) MD 10,279 10,085 9,506 9,16010,344 9,994 10,532 11,157 TD 7,233 7,140 6,100 7,004 6,870 7,678 7,9918,064 Elmendorf Tear MD (g) 369 347 393 446 464 384 227 361 TD (g) 411413 436 460 488 444 307 339 MD (g/mil) 567 488 554 637 737 541 330 516TD (g/mil) 652 582 606 657 650 609 446 477 Dart Drop Method A (g) 590542 590 572 590 584 410 590 (g/mil) 843 809 855 829 855 834 621 868Puncture Break 25.83 25.54 22.84 23.97 23.10 24.65 46.57 35.53 Energy(in-lbs/mil)

TABLE 6 Example- Example- Example- Example- Example- Example-Comparative- Comparative- 1a 2a 3a 4a 5a 6a 1a 4a 12 (g/10 min) 1.0 1.01.0 0.7 0.7 0.5 1.0 0.5 MIR 35 40 54 44 53 49 16 26 Density 0.922 0.9220.922 0.922 0.922 0.917 0.919 0.917 (g/cm3) Nominal 0.7 0.7 0.7 0.7 0.70.7 0.7 0.7 gauge (mil) Die gap 60 60 60 60 60 60 60 60 (mil) BUR 2.52.5 2.5 2.5 2.5 2.5 2.5 2.5 FLH (in) 33 33 33 33 33 37 37 Melt 424.7412.5 404 427.8 409.9 438.4 456 Temperature (F.) Air ring, 40 40.5 40.542.5 42.5 46 41 % air Extruder 117 109.7 112.2 114.4 109.2 118.5 101.7RPM Rate (lb/hr) 300 300 300 300 300 300 300 Lb/hr/RPM 2.56 2.7 2.67 3.33.3 2.53 2.95 Head 5850 5780 5298 6338 5872 6789 7135 pressure (psi)Motor load 53 53.1 49.5 55.1 52.1 55.3 66 (%)

Films of 1.0 mil thickness were made for each of the polymers of Table 1under the conditions set forth in Table 8. The properties of such filmsare reported in Table 7.

TABLE 7 Example- Example- Example- Example- Example- Example-Comparative- Comparative- 1b 2b 3b 4b 5b 6b 1b 4b TDA (ppm) > 15 5 5 6 210 15 200 micr 12 (g/10 min) 1.0 1.0 1.0 0.7 0.7 0.5 1 0.5 MIR 35 40 5444 53 49 16 26 Density 0.922 0.922 0.922 0.922 0.922 0.917 0.919 0.917(g/cm3) Gauge Mic (mils) Average 1.03 1.02 1.04 1.08 1.06 1.08 1.01 1.011% Secant (psi) MD 34,005 35,360 33,747 35,157 34,888 29,859 24,65527,533 TD 44,028 45,918 51,575 46,934 50,437 43,514 27,539 33,681Tensile Yield Strength (psi) MD 1,576 1,573 1,547 1,593 1,553 1,3921,398 1,339 TD 1,771 1,831 1,927 1,880 1,837 1,587 1,377 1,501 TensileStrength (psi) MD 8,919 8,672 8,627 9,361 8,758 9,730 9,844 10,628 TD7,609 7,876 6,507 7,526 6,889 7,624 8,229 8,298 Elmendorf Tear MD (g)293 254 112 376 268 335 241 419 TD (g) 538 524 555 615 626 594 413 474MD (g/mil) 287 247 107 369 260 322 236 419 TD (g/mil) 527 499 544 569590 576 409 456 Haze (%) 19.8 25.8 >30 >30 >30 >30 17 8.9 Haze-internal3.4 4.2 4.1 3.7 4.2 3.5 1.9 2.4 (%) Gloss MD 10.9 8.1 5.7 7.2 4.6 4.014.3 22.4 TD 11.1 8.2 5.9 7.2 4.6 3.9 15.0 21.0 Dart Drop Method A (g)782 842 608 794 818 926 830 1034 (g/mil) 759 825 585 735 772 857 8221024 Puncture Break Energy 28.69 24.66 21.45 20.14 19.94 26.60 46.3339.23 (in-lbs/mil)

TABLE 8 Example- Example- Example- Example- Example- Example-Comparative- Comparative- 1a 2a 3a 4a 5a 6a 1a 4a 12 (g/10 min) 1.0 1.01.0 0.7 0.7 0.5 1.0 0.5 MIR 35 40 54 44 53 49 16 26 Density 0.922 0.9220.922 0.922 0.922 0.917 0.919 0.917 (g/cm3) Nominal 1 1 1 1 1 1 1 1gauge (mil) Die gap 60 60 60 60 60 60 60 60 (mil) BUR 2.5 2.5 2.5 2.52.5 2.5 2.5 2.5 FLH (in) 23 23 23 22 21 23 26 23 Melt 409.3 403.2 396.3413.2 400.9 425.3 433.4 462.7 Temperature (F.) Air ring, 41.5 41.5 41.549 49 50 34.5 49 % air Extruder 78.3 75.7 75.4 77.7 74.2 83.2 78 94.2RPM Rate (lb/hr) 198 198 198 198 198 198 198 198 Lb/hr/RPM 2.53 2.622.63 2.55 2.67 2.38 2.54 2.1 Head 4667 4557 4227 5221 4708 5606 55436531 pressure (psi) Motor load 48.4 47.8 45.7 49.9 47.9 50 52.3 50 (%)

FIG. 2 shows the average MD/TD film modulus as a function of resinsdensity for comparative and inventive examples. Note that the inventivefilms have an average MD/TD modulus that is greater than X, whereX=(2,065,292*density)−1,872,345. This indicates that the inventiveexamples exhibited a substantial advantage in film stiffness at a givenresin density.

The phrases, unless otherwise specified, “consists essentially of” and“consisting essentially of” do not exclude the presence of other steps,elements, or materials, whether or not, specifically mentioned in thisspecification, so long as such steps, elements, or materials, do notaffect the basic and novel characteristics of the invention,additionally, they do not exclude impurities and variances normallyassociated with the elements and materials used.

For the sake of brevity, only certain ranges are explicitly disclosedherein. However, ranges from any lower limit may be combined with anyupper limit to recite a range not explicitly recited, as well as, rangesfrom any lower limit may be combined with any other lower limit torecite a range not explicitly recited, in the same way, ranges from anyupper limit may be combined with any other upper limit to recite a rangenot explicitly recited. Additionally, within a range includes everypoint or individual value between its end points even though notexplicitly recited. Thus, every point or individual value may serve asits own lower or upper limit combined with any other point or individualvalue or any other lower or upper limit, to recite a range notexplicitly recited.

All priority documents are herein fully incorporated by reference forall jurisdictions in which such incorporation is permitted and to theextent such disclosure is consistent with the description of the presentinvention. Further, all documents and references cited herein, includingtesting procedures, publications, patents, journal articles, etc. areherein fully incorporated by reference for all jurisdictions in whichsuch incorporation is permitted and to the extent such disclosure isconsistent with the description of the present invention.

While the invention has been described with respect to a number ofembodiments and examples, those skilled in the art, having benefit ofthis disclosure, will appreciate that other embodiments can be devisedwhich do not depart from the scope and spirit of the invention asdisclosed herein.

What is claimed is:
 1. A polyethylene composition comprising at least 65wt % ethylene derived units and from 0 to 35 wt % of C3-C12 olefincomonomer derived units, based upon the total weight of the polyethylenecomposition; wherein the polyethylene composition has: a) an RCI,m of150 kg/mol or greater; and one or both of: b) a Tw₁-Tw₂ value of from−16 to −38° C.; and c) an Mw₁/Mw₂ value of at least 0.9; and one or moreof the following: d) a density of from 0.890 g/cm³ to 0.940 g/cm³; e) amelt index (MI) of from 0.1 g/10 min to 30 g/10 min; f) a melt indexratio (121/12) of from 10 to 90; g) an M_(w)/M_(n) of from 2 to 16; h)an M_(z)/M_(w) of from 2.5 to 5.0; i) an M_(z)/M_(n) of from 10 to 50;and j) a g′(vis) of 0.90 or greater; and further wherein the internalunsaturation of the polyethylene composition as measured by ¹H NMR ismore than 0.2 total internal unsaturations per thousand carbon atoms. 2.The polyethylene composition of claim 1, wherein the C₃-C₁₂ olefincomonomer derived units are C₄-C₈ α-olefin comonomer derived units. 3.The polyethylene composition of claim 1, wherein the polyethylenecomposition comprises from 0.5 to 20 wt % of the C₃-C₁₂ olefin comonomerderived units, based upon the total weight of the polyethylenecomposition.
 4. The polyethylene composition of claim 1, wherein thepolyethylene composition comprises from 1 to 10 wt % of C₄-C₈ α-olefincomonomer derived units, based upon the total weight of the polyethylenecomposition.
 5. The polyethylene composition of claim 1, wherein thepolyethylene composition has a Tw₁-Tw₂ value of from −23 to −36° C. 6.The polyethylene composition of claim 1, wherein the polyethylenecomposition has a Tw₁-Tw₂ value of from −23 to −33° C.
 7. Thepolyethylene composition of claim 1, wherein the polyethylenecomposition has an Mw₁/Mw₂ value of from 0.9 to
 4. 8. The polyethylenecomposition of claim 1, wherein the polyethylene composition has anMw₁/Mw₂ value of from 1.25 to
 4. 9. The polyethylene composition ofclaim 1, wherein the polyethylene composition has a melt index (MI) offrom 0.1 g/10 min to 6 g/10 min.
 10. The polyethylene composition ofclaim 1, wherein the polyethylene composition has a melt index ratio(I₂₁/I₂) of from 20 to
 45. 11. The polyethylene composition of claim 1,wherein the polyethylene composition has a high load melt index (I₂₁) offrom 5 to 60 g/10 min.
 12. The polyethylene composition of claim 1,wherein the polyethylene composition has an M_(w)/M_(n) of from 5 to10.5.
 13. The polyethylene composition of claim 1, wherein thepolyethylene composition has a g′(vis) of 0.940 or greater.
 14. Thepolyethylene composition of claim 1, wherein the polyethylenecomposition has a density of from 0.900 g/cm³ to 0.930 g/cm³.
 15. Thepolyethylene composition of claim 1, wherein the polyethylenecomposition has an RCI,m of 200 kg/mol or greater.
 16. The polyethylenecomposition of claim 1, having all of the properties (d)-(j).
 17. Anarticle made from the polyethylene composition of claim 1, wherein thearticle is optionally a blown film or cast film.
 18. A film made fromthe polyethylene composition of claim 1, wherein the film has an averageMD/TD modulus 1.2*X or more, where X=(2,065,292*density of polyethylenecomposition)−1,872,345.
 19. The article of claim 17, wherein the filmexhibits an average MD/TD modulus of between 30,000 psi and 40,000 psi.20. The article of claim 17, wherein the film has a dart drop impactresistance of 600 g/mil or greater.
 21. The article of claim 17, whereinthe film has a dart drop impact resistance of 700 g/mil or greater. 22.The article of claim 17, wherein the film has an Elmendorf tearresistance of 300 g/mil or greater in the machine direction (MD). 23.The article of claim 17, wherein the film has an Elmendorf tearresistance of 350 g/mil or greater in the machine direction (MD). 24.The article of claim 17, wherein the film has a haze of 12% or less. 25.The article of claim 17, wherein the polymer composition has an MIR of35 to 55 and wherein the film has an Elmendorf tear resistance of 300g/mil or more in the machine direction (MD), and/or a dart drop impactresistance of at least 500 g/mil or more.